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Question 221Question →

Arrange the following key historical events leading up to and solidifying the implementation of Nigeria's 1960 Independence Constitution in chronological order from earliest to latest.

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Answer

The correct chronological sequence is: (1) The Resumed Constitutional Conference in London (1958), followed by (2) The imperial passage of the Nigeria Independence Act by the British Parliament (July 1960), then (3) The formal coming into effect of the 1960 Independence Constitution (October 1, 1960), and finally (4) The assumption of office by Dr. Nnamdi Azikiwe as Governor-General (November 1960).
The sequence follows historical progression: The Resumed Constitutional Conference in London (1958) finalized constitutional structures and minority safeguards. The British Parliament subsequently enacted the Nigeria Independence Act in July 1960 to transfer sovereign authority. The 1960 Independence Constitution officially took effect on October 1, 1960. Finally, Dr. Nnamdi Azikiwe assumed office as the first indigenous Governor-General in November 1960, succeeding Sir James Robertson.

Step-by-Step Solution

1
Determine the date of the Resumed London Constitutional Conference.
Identified that the conference took place in late 1958.
Constitutional negotiation and agreements on independence dates preceded parliamentary enactment.
2
Determine when the British Parliament enacted the Nigeria Independence Act.
Identified that the imperial legislation was passed in July 1960.
Statutory authority from the colonial power was required prior to independence day.
3
Determine the commencement date of the Independence Constitution.
Identified that the constitution took effect on October 1, 1960.
October 1, 1960, marked the formal transition of Nigeria into an independent federal state.
4
Determine when Dr. Nnamdi Azikiwe became Governor-General.
Identified that Azikiwe took office in November 1960.
Sir James Robertson served as Governor-General on October 1, 1960, with Azikiwe assuming office a month later.

Key Concept

Chronological development and implementation milestones of the 1960 Independence Constitution.
Question 222Question →

A Nigerian importer enters into a contract to purchase heavy equipment from a manufacturer in Japan using a Confirmed Irrevocable Letter of Credit. What is the correct chronological sequence of operational steps required to successfully execute and settle this foreign trade payment mechanism from start to finish?

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Answer

The correct chronological order begins with the buyer applying to the issuing bank for a letter of credit, followed by international bank transmission and confirmation to the seller, shipment of goods and procurement of the Bill of Lading by the seller, document verification and payment by the intermediary bank, and finally buyer reimbursement to receive the title documents.
The procedural sequence follows standard international trade rules (UCP 600) for documentary credits. Credit application establishes financial backing; bank advising informs the seller; shipment produces the Bill of Lading; document presentation triggers bank settlement; and bank reimbursement releases title documents to the buyer.

Step-by-Step Solution

1
Identify the initiation phase of foreign payment under documentary credit.
The importer applies to the issuing bank in Nigeria to open the Letter of Credit.
Commercial banks act on behalf of buyers to initiate credit guarantees prior to shipment.
2
Trace the inter-bank notification and confirmation workflow.
The issuing bank sends credit details to the Japanese correspondent bank to advise and confirm to the exporter.
A confirmed letter of credit requires a bank in the exporter's country to assume payment liability alongside the issuing bank.
3
Determine exporter performance and document generation.
The exporter consigns goods, receives the Bill of Lading, and presents documents to the negotiating bank.
The Bill of Lading is the primary document of title generated upon loading goods onto the vessel.
4
Evaluate document checking and payment settlement to the exporter.
The negotiating bank inspects documents for compliance and releases payment to the exporter.
Under Uniform Customs and Practice for Documentary Credits (UCP), banks deal in documents, not goods, paying upon strict compliance.
5
Identify the final settlement and transfer of title to the importer.
The issuing bank collects payment from the importer and hands over the Bill of Lading for port clearance.
The buyer cannot take delivery of cargo at destination without presenting the original endorsed Bill of Lading.

Key Concept

Operational Workflow of Confirmed Irrevocable Letters of Credit in Foreign Trade
Question 223Question →

To evaluate the escalating political tensions that ultimately led to the collapse of Nigeria's First Republic, place the following historical developments in chronological order from the earliest to the latest event.

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Answer

The correct chronological order of events is: first, the declaration of a state of emergency in the Western Region (May 1962); second, the national population census crisis (1962–1963); third, the formation of the NNA and UPGA political alliances (1964); and fourth, the outbreak of electoral violence in the Western Region ('Operation Wetie') in late 1965.
The correct chronological timeline begins with the Action Group crisis and Western Region emergency rule in May 1962, followed by the national population census conflict of 1962–1963, then the realignment of parties into NNA and UPGA in mid-1964, and concludes with the widespread violence of 'Operation Wetie' after the October 1965 Western Region elections.

Step-by-Step Solution

1
Identify the timeframe for the Action Group crisis and Western Region emergency rule.
The factional division within the Action Group led to the federal declaration of a state of emergency in May 1962.
This event signaled the first major federal intervention in regional governance after independence.
2
Determine the sequence of the Census crisis.
Demographic controversies over the 1962 enumeration led to its cancellation and a contested 1963 recount.
Census figures determined regional representation and political dominance in the federal parliament.
3
Trace the formation of broad political alliances ahead of the federal election.
The Nigerian National Alliance (NNA) and the United Progressive Grand Alliance (UPGA) were established in 1964.
Regional parties regrouped into macro-alliances to contest the December 1964 federal legislative elections.
4
Pinpoint the final regional election crisis.
Widespread civil unrest ('Operation Wetie') erupted following the October 1965 Western Regional elections.
Allegations of massive electoral malpractice led to arson and unrest, delivering the final blow to the First Republic.

Key Concept

Chronology of Political Crises in Nigeria's First Republic (1960–1966)
Question 224Question →

In classical prose narrative design (Freytag's pyramid), plot progression follows a defined sequence of structural stages. Arrange the following narrative plot stages in chronological order, starting from the beginning of a story to its final outcome.

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Answer

The correct chronological order of plot progression is Exposition, Rising Action, Climax, Falling Action, and Resolution (Denouement).
In standard prose narrative architecture, plot events move logically from establishing background context (exposition), to increasing dramatic conflict (rising action), reaching the crisis peak (climax), easing tension through consequences (falling action), and settling all complications in the final outcome (resolution).

Step-by-Step Solution

1
Identify the initial narrative stage.
Exposition is established first as it introduces the baseline context, characters, and setting.
A narrative requires initial context before conflict can develop.
2
Identify the development stage of conflict.
Rising Action follows the exposition as an inciting incident occurs and obstacles escalate tension.
Conflict builds progressively after the initial baseline is set.
3
Locate the peak moment of crisis.
Climax is positioned as the central turning point.
The escalating tension of the rising action culminates in the peak moment of maximum confrontation.
4
Determine the de-escalation of tension.
Falling Action occurs immediately after the climax.
Tension subsides as characters navigate the direct fallout of the climax.
5
Identify the narrative conclusion.
Resolution (Denouement) marks the final stage.
Plot complications are settled, restoring order or establishing a new status quo.

Key Concept

Classical Plot Structure (Freytag's Pyramid)
Estimated Time:1m 30s
Question 225Question →

Arrange the following stages of a traditional distribution channel in the correct order, starting from the original producer down to the final consumer.

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Answer

The correct sequence starts with the manufacturer producing goods in bulk, followed by the wholesaler purchasing in bulk for warehousing, then the retailer buying smaller quantities to stock local shelves, and ends with the consumer buying individual units.
In home trade, goods flow sequentially from the manufacturer (production), to the wholesaler (bulk-breaking and warehousing), to the retailer (convenient local selling), and finally to the consumer (end use).

Step-by-Step Solution

1
Identify the origin of trade goods
The manufacturer produces goods in large quantities.
Distribution begins at the production stage before middleman intervention.
2
Identify the primary wholesale intermediary function
The wholesaler purchases in bulk and stores the goods in a central warehouse.
Wholesalers buy directly from producers to provide bulk-breaking and storage functions.
3
Identify the retail middleman function
The retailer buys smaller quantities from the wholesaler to stock local shop shelves.
Retailers depend on wholesalers to supply varied inventory in manageable lot sizes.
4
Identify the ultimate endpoint of distribution
The consumer buys individual units from the retailer for personal use.
The final consumer acquires goods from retail outlets to satisfy end consumption needs.

Key Concept

Traditional Channel of Distribution Flow
Question 226Question →

A commercial enterprise receives a consignment of foreign manufactured goods at a sea terminal. In what chronological sequence should the following steps be carried out to clear these goods through customs control?

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Answer

The correct chronological sequence for customs clearance is: Submission of import documentation → Physical examination of cargo → Assessment of tariff duties → Payment of assessed duties → Issuance of customs release order.
Customs control requires a structured procedure beginning with document submission to declare the cargo, physical inspection to confirm declarations, duty assessment based on cargo verification, duty payment settlement, and concluding with the official release order.

Step-by-Step Solution

1
Submit import documents to customs
The import declaration is logged with customs authorities.
Customs requires shipping documents to identify the nature and value of incoming goods.
2
Inspect cargo at port of entry
Physical goods are verified against declared descriptions.
Prevents under-declaration, false documentation, and importation of restricted items.
3
Calculate customs duty liability
The precise tariff amount payable is determined.
Customs tariff rates depend on accurate classification and valuation of inspected goods.
4
Settle tariff duty payment
Financial obligation to the government is fulfilled.
Goods remain under customs custody until statutory duties are cleared.
5
Obtain customs release order
The importer receives official authorization to retrieve the cargo from port custody.
This represents the final clearance step ending customs restriction on the shipment.

Key Concept

Customs Clearance Sequence and Control in Foreign Trade
Question 227Question →

In the pre-colonial Yoruba political system of the Oyo Empire, a formal constitutional procedure was followed by the Oyomesi to depose an autocratic Alaafin (Oba). Arrange the following stages of this deposition process in their correct chronological order from first to last.

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Answer

The correct chronological sequence for deposing an autocratic Alaafin is: first, the Oyomesi convenes in secret under the Bashorun; second, a vote of no confidence is passed; third, the Bashorun presents a calabash containing parrot's eggs as a symbol of rejection; fourth, the Alaafin commits ritual suicide.
The removal of a tyrant Oba in pre-colonial Oyo followed a strict constitutional sequence. The process initiated with the secret convening of the Oyomesi led by the Bashorun. Once a vote of no confidence was reached, the Bashorun delivered a covered calabash containing parrot's eggs, symbolizing total rejection by the community, ancestors, and deities. Finally, custom required the deposed Alaafin to commit ritual suicide to preserve institutional stability and vacate the throne.

Step-by-Step Solution

1
Identify the initial council assembly stage.
The procedure commences when the Oyomesi holds a secret meeting chaired by the Bashorun.
Constitutional grievances against executive tyranny must first be formally raised within the council of state.
2
Determine the internal decision-making outcome.
The Oyomesi adopts a resolution of no confidence.
A consensus among kingmakers is required before invoking traditional rejection rituals.
3
Identify the symbolic notification of rejection.
The Bashorun sends the symbolic calabash containing parrot's eggs to the Alaafin.
This serves as the official constitutional notice that the monarch's divine mandate has been revoked.
4
Identify the final constitutional outcome.
The Alaafin performs ritual suicide.
In Yoruba tradition, a rejected Oba cannot continue to live or rule, ensuring the complete vacation of executive power.

Key Concept

Constitutional Checks and Balances in the Yoruba Political System
Question 228Question →

Arrange the following steps in the correct statutory sequence for settling accounts and distributing assets upon the dissolution of a partnership firm, from first to last.

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Answer

The correct statutory order for distributing assets upon partnership dissolution is: first, paying external third-party creditors; second, settling partner loans and advances; third, returning partner capital contributions; and fourth, distributing any remaining surplus in the agreed profit-sharing ratio.
Under standard commercial law (Section 44 of the Partnership Act), the settlement of accounts upon dissolution follows a strict hierarchy: external third-party liabilities are paid first, followed by partner loans and advances, then partner capital refunds, and finally the distribution of any remaining surplus among partners according to their agreed profit-sharing ratio.

Step-by-Step Solution

1
Discharge external liabilities
Debts owed to outside creditors and suppliers are fully paid.
Outside creditors hold primary legal claims against the firm's assets.
2
Settle partner loans and advances
Money lent to the firm by partners beyond their capital contributions is repaid.
Partner loans are treated as debt obligations taking precedence over equity capital repayment.
3
Refund partner capital accounts
Capital contributed by each partner is returned.
Equity capital is returned to owners only after all debt claims (external and internal) are cleared.
4
Divide the residual surplus
Remaining net assets are distributed among partners based on their profit-sharing ratio.
Partners receive residual profits in their capacity as equity owners.

Key Concept

Statutory Sequence of Asset Distribution upon Partnership Dissolution
Estimated Time:1m 15s
Question 229Question →

A merchant wholesaler plays a pivotal role in connecting large-scale producers with small-scale retailers. Arrange the following operational stages of a merchant wholesaler in their correct chronological sequence, from initial interaction with manufacturers to final delivery to retail outlets.

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Answer

The correct sequence is: acquiring bulk consignments and legal title from manufacturers, storing bulk inventory in regional warehouses, breaking bulk into smaller commercial packages, and extending trade credit while distributing smaller packages to local retailers.
The logical sequence of wholesale operations begins with acquiring bulk consignments and legal title from manufacturers. Next, the wholesaler transports and stores these bulk goods in regional warehouses to ensure steady market supply. Afterwards, the wholesaler performs bulk-breaking by unpacking, sorting, and repacking goods into smaller lots. Finally, the wholesaler sells these smaller packages to local retailers, frequently extending short-term trade credit and providing delivery services.

Step-by-Step Solution

1
Identify the primary transaction between manufacturer and wholesaler.
Acquiring bulk shipments and assuming legal title is step 1.
The wholesaler must first buy in bulk and accept ownership risk before handling or selling the products.
2
Determine the immediate logistics requirement after purchase.
Warehousing and inventory storage is step 2.
Bulk goods must be safely stored in central facilities to bridge the time gap between production and market demand.
3
Identify the preparation step needed before selling to smaller traders.
Breaking bulk, sorting, and grading is step 3.
Retailers cannot afford or store full factory consignments, so goods must be divided into smaller lots.
4
Identify the final transaction that completes the wholesale function.
Granting trade credit and delivering smaller quantities to retailers is step 4.
This step completes the channel flow by placing manageable quantities of goods into retail hands.

Key Concept

Sequential Functions of Wholesalers in the Channel of Distribution
Estimated Time:2m 0s
Question 230Question →

Arrange the following key historical events of the Nigerian Civil War era (1967–1970) in their correct chronological sequence, from earliest to latest:

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Answer

The correct chronological order of events is: Aburi Peace Conference (January 1967) → Creation of 12 states (May 27, 1967) → Declaration of the Republic of Biafra (May 30, 1967) → Outbreak of military hostilities at Garkem (July 6, 1967).
The correct sequence begins with the Aburi Conference in January 1967, followed by the federal decree creating 12 states on May 27, 1967, the declaration of Biafra on May 30, 1967, and finally the outbreak of military hostilities at Garkem on July 6, 1967.

Step-by-Step Solution

1
Identify the date of the Aburi Peace Conference.
January 1967.
This meeting was held in Ghana prior to any territorial restructuring or military action.
2
Determine the date of General Gowon's state creation decree.
May 27, 1967.
The Federal Military Government abolished the regional arrangement in favor of a 12-state federation.
3
Identify the date of Biafra's secession declaration.
May 30, 1967.
Lt. Col. Ojukwu declared Eastern Nigeria as the sovereign Republic of Biafra three days after the state creation decree.
4
Establish the date when active combat began.
July 6, 1967.
Federal troops initiated military operations at Garkem to force Biafra back into the federation.

Key Concept

Pre-war chronological progression of diplomatic breakdown and conflict triggers in Nigeria (1967)
Question 231Question →

Arrange the following historical forms of money in chronological order from the earliest to the most modern form.

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Answer

The correct chronological sequence from earliest to most modern is: Commodity money, Metallic money, Paper banknotes, and Electronic money.
The correct order follows the historical evolution of trade exchange media: from primitive commodity items to precious metallic coins, then lightweight paper banknotes, and finally computer-based electronic money.

Step-by-Step Solution

1
Identify the earliest form of money used directly after the barter system.
Commodity money (salt, cowries, cattle) is position 1.
Before metal minting existed, useful physical commodities were used directly as media of exchange.
2
Identify the form of money created to overcome the bulky nature of commodities.
Metallic money (gold, silver coins) is position 2.
Metals provided standard unit values and durability superior to raw commodities.
3
Identify the transition to lightweight currency backed by guarantees.
Paper banknotes are position 3.
Paper notes developed as receipts for stored metallic money, eventually evolving into legal tender fiat currency.
4
Identify the contemporary digital medium of exchange.
Electronic money is position 4.
Modern banking relies on digital transfers and electronic credits, forming the latest stage of monetary evolution.

Key Concept

Historical Evolution of Forms of Money
Question 232Question →

A public limited company intends to raise long-term equity capital by issuing new shares to the public on the primary capital market. What is the correct chronological sequence of steps involved in completing this initial public offering process?

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Answer

The correct sequence starts with the publication of the prospectus, followed by investor application submission, followed by share allotment by the issuing house, and concludes with listing the shares for trading on the stock exchange.
The issuance of new securities in the primary capital market begins with publishing a regulatory prospectus to inform the public. Interested investors then apply and deposit subscription monies. After the subscription window closes, the issuing house processes share allotment and returns funds from oversubscriptions. Finally, the newly created shares are listed on the secondary market (stock exchange) to enable subsequent trading among investors.

Step-by-Step Solution

1
Identify the initial disclosure requirement for raising capital from the public.
The company releases the approved prospectus inviting subscriptions.
Regulatory bodies and investors require full financial disclosure before capital can be solicited.
2
Determine the investor response phase.
Investors complete application forms and deposit funds with designated receiving banks.
This represents the primary market subscription phase.
3
Identify the post-subscription processing stage.
The issuing house completes share allotment and dispatches certificates/CSCS accounts notifications.
Ownership rights are formally assigned to applicants based on availability.
4
Determine the final market entry stage.
The shares are admitted to the official listing of the stock exchange for secondary trading.
Listing provides liquidity, allowing shareholders to sell their holdings on the secondary market.

Key Concept

Primary Capital Market Public Share Issuance Process
Question 233Question →

A chemist is given a dry solid mixture containing nickel powder, ammonium chloride (NH4ClNH_4Cl), fine barium sulfate (BaSO4BaSO_4) powder, and sodium chloride (NaClNaCl). What is the correct chronological sequence of laboratory procedures required to isolate each pure component from the mixture?

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Answer

The correct sequence of separation steps is: 1. Pass a magnet over the dry solid mixture to isolate nickel powder. 2. Heat the dry residue to sublime ammonium chloride. 3. Add distilled water to dissolve sodium chloride. 4. Centrifuge the suspension to spin down fine barium sulfate powder. 5. Decant the clear supernatant liquid and evaporate to dryness to recover sodium chloride crystals.
The correct sequence begins with magnetization on the dry solid mixture to remove ferromagnetic nickel. Next, sublimation is performed on the dry residue to separate ammonium chloride, which must occur before adding water because both ammonium chloride and sodium chloride are water-soluble. Distilled water is then added to selectively dissolve sodium chloride while leaving barium sulfate in suspension. Centrifugation rapidly spins down the fine barium sulfate precipitate. Finally, decanting and evaporating the clear supernatant liquid yields pure sodium chloride crystals.

Step-by-Step Solution

1
Extract ferromagnetic nickel powder using a bar magnet.
Dry nickel powder is separated cleanly from the solid mixture.
Nickel is ferromagnetic and is attracted by a magnetic field without requiring chemical reagents or solvent addition.
2
Apply controlled heat to the dry residue under an inverted funnel to sublime ammonium chloride (NH4ClNH_4Cl).
Ammonium chloride sublimates directly into gas upon heating and deposits as pure solid crystals on the cool funnel surface.
Sublimation must precede water dissolution because both NH4ClNH_4Cl and NaClNaCl are soluble in water; dissolving first would make thermal separation of the two salts impossible.
3
Add distilled water to the remaining mixture of NaClNaCl and BaSO4BaSO_4 and stir.
Sodium chloride dissolves into aqueous solution (NaCl(aq)NaCl_{(aq)}) while insoluble BaSO4BaSO_4 forms a fine suspension.
Water acts as a selective solvent based on solubility differences between soluble NaClNaCl and insoluble BaSO4BaSO_4.
4
Spin the suspension in a laboratory centrifuge.
Dense, fine particles of BaSO4BaSO_4 compact tightly at the bottom of the tube, separating clearly from the aqueous liquid.
Centrifugation rapidly forces fine suspended solids out of liquid phase much faster and more completely than gravity filtration.
5
Decant the supernatant solution and evaporate the solvent.
Water evaporates off, yielding pure crystalline sodium chloride.
Evaporation separates a non-volatile soluble solid solute from its volatile liquid solvent.

Key Concept

Sequential Separation of Multi-Component Mixtures
Question 234Question →

Arrange the following structural phases of dramatic plot development in their correct sequential order from the beginning of a play to its final outcome:

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Answer

The correct dramatic sequence begins with the Exposition, followed by the Inciting Incident, Rising Action, Climax, and finishes with the Denouement.
In classical dramatic structure (Freytag's Pyramid), a play begins with the Exposition to establish context, moves into the Inciting Incident which launches the conflict, escalates through the Rising Action, hits its peak at the Climax, and resolves during the Denouement.

Step-by-Step Solution

1
Identify the initial dramatic setup.
Exposition is established as the starting point where background information and characters are introduced.
Dramatic structure requires background context before action occurs.
2
Determine the trigger for dramatic tension.
Inciting Incident acts as the second phase.
A specific catalyst must disrupt the initial equilibrium to begin the central conflict.
3
Trace the escalation of conflicts.
Rising Action follows the catalyst.
Complications build upon the central conflict to heighten dramatic suspense.
4
Locate the turning point of maximum tension.
Climax is placed after the rising action.
The plot reaches a critical peak where the protagonist faces the central problem directly.
5
Conclude the structural trajectory.
Denouement forms the final phase.
Following the climax, the narrative unravels toward resolution and closure.

Key Concept

Freytag's Pyramid / Dramatic Structure
Question 235Question →

A student is provided with a crude sample of rock salt containing sodium chloride (NaClNaCl) contaminated with insoluble calcium carbonate (CaCO3CaCO_3) and sand (SiO2SiO_2). Arrange the following laboratory procedures in the correct sequence to obtain pure, dry crystals of sodium chloride from this mixture.

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Answer

The correct sequence of procedures is: First, grind the sample and dissolve it in distilled water. Next, filter the mixture to separate the insoluble solids from the NaClNaCl filtrate. Then, heat the filtrate to its crystallization point to obtain a saturated solution. After that, cool the solution slowly to allow crystal formation. Finally, filter and dry the crystals between filter papers.
The correct order follows the standard laboratory procedure for recovering a pure salt from a mixture containing insoluble solids: dissolution →\rightarrow filtration →\rightarrow evaporation to crystallization point →\rightarrow cooling →\rightarrow final filtration and drying.

Step-by-Step Solution

1
Dissolution of soluble component
Sodium chloride dissolves in distilled water while sand and calcium carbonate remain undissolved solids.
Solubility differences allow selective dissolution of NaClNaCl from insoluble impurities.
2
Gravity filtration
Insoluble sand and CaCO3CaCO_3 are retained on the filter paper as residue; aqueous NaClNaCl passes through as filtrate.
Filtration separates insoluble solids from aqueous solutions.
3
Controlled evaporation to saturation point
Water evaporates until the NaClNaCl solution reaches saturation (crystallization point).
Heating to dryness should be avoided when pure crystals are desired, as rapid evaporation can trap impurities or spur spitting.
4
Controlled cooling and crystallization
Well-defined crystals of sodium chloride precipitate out of the cooling solution.
Solubility decreases with lowering temperature, allowing solute molecules to arrange into crystal lattices.
5
Isolation and drying of crystals
Pure, dry crystals of NaClNaCl are collected.
Filtering removes the remaining mother liquor containing residual soluble contaminants, and filter paper absorbs surface moisture.

Key Concept

Multi-step purification of a soluble salt from insoluble impurities using dissolution, filtration, evaporation to saturation, and crystallization.
Estimated Time:2m 0s
Question 236Question →

A laboratory mixture consists of an organic solute dissolved in water. A chemist decides to isolate the organic solute by solvent extraction using ethoxyethane (diethyl ether). Arrange the following procedural steps in the correct logical sequence from first to last to complete this separation using a separating funnel.

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Answer

The correct logical sequence is: first, close the stopcock and introduce the aqueous mixture and ethoxyethane into the funnel; second, stopper, invert, shake, and periodically vent internal pressure; third, mount the funnel on a stand and allow the immiscible layers to settle completely; fourth, remove the stopper and carefully drain the lower aqueous layer followed by collecting the upper organic layer.
The correct procedural order follows standard chemical laboratory protocol: loading reagents, mixing/partitioning with pressure venting, phase settling via density separation, and step-by-step draining under atmospheric pressure.

Step-by-Step Solution

1
Ensure the stopcock is closed and add both liquid phases into the separating funnel.
Both liquids are safely contained inside the funnel without draining prematurely.
Solvent extraction requires bringing the solute-containing mixture into contact with the extraction solvent.
2
Stopper the funnel, invert it, shake thoroughly, and open the stopcock repeatedly while inverted.
Interfacial contact area is maximized for solute partitioning, and excess vapor pressure is safely released.
Agitation allows the solute to dissolve into the organic phase, while venting avoids dangerous pressure buildup from volatile solvents.
3
Place the funnel back on a retort stand and let it rest undisturbed.
The mixture separates into two distinct liquid layers based on density and immiscibility.
Static resting is necessary for the dispersed droplets of the two immiscible liquids to coalesce into continuous phases.
4
Unstopper the funnel and open the stopcock to drain the bottom aqueous layer into a flask, then separate the upper ethoxyethane layer.
The two liquids are cleanly separated into individual collection vessels.
Unstoppering equalizes atmospheric pressure to prevent a vacuum lock during draining.

Key Concept

Solvent Extraction and Separating Funnel Manipulation
Question 237Question →

Arrange the following atomic subshells in order of increasing energy according to the Aufbau principle ((n+l)(n+l) rule):

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Answer

The correct order of increasing orbital energy is 3s→3p→4s→3d3s \rightarrow 3p \rightarrow 4s \rightarrow 3d.
By applying the (n+l)(n+l) rule (Madelung's rule) derived from the Aufbau principle, subshells fill in order of increasing (n+l)(n+l) energy sum. Calculating these values yields: 3s3s (3+0=33+0=3), 3p3p (3+1=43+1=4), 4s4s (4+0=44+0=4), and 3d3d (3+2=53+2=5). For subshells with equal sums (3p3p and 4s4s), the one with the smaller principal quantum number nn is lower in energy (3p3p with n=3n=3 is lower than 4s4s with n=4n=4). Therefore, the correct sequence from lowest to highest energy is 3s→3p→4s→3d3s \rightarrow 3p \rightarrow 4s \rightarrow 3d.

Step-by-Step Solution

1
Determine the (n+l)(n+l) value for each subshell
For 3s3s: 3+0=33+0 = 3. For 3p3p: 3+1=43+1 = 4. For 4s4s: 4+0=44+0 = 4. For 3d3d: 3+2=53+2 = 5.
According to the Aufbau principle and the (n+l)(n+l) rule, orbitals fill in order of increasing (n+l)(n+l) energy values.
2
Compare subshells with identical (n+l)(n+l) values
Both 3p3p and 4s4s have (n+l)=4(n+l) = 4. Since 3p3p has a smaller principal quantum number (n=3n=3 compared to n=4n=4), 3p3p is lower in energy than 4s4s.
When two orbitals have the same (n+l)(n+l) value, the orbital with the lower principal quantum number nn has lower energy.
3
Sequence the subshells from lowest to highest energy
The final sequence is 3s<3p<4s<3d3s < 3p < 4s < 3d.
Sorting by (n+l)(n+l) sum first, then by nn value for ties, yields the correct Aufbau order.

Key Concept

Aufbau Principle and the (n+l) Rule
Question 238Question →

Arrange the following steps in the correct chronological order to illustrate how water hardness is removed using the zeolite (permutit) ion-exchange method and how the column is subsequently regenerated.

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Answer

The correct sequence for removing water hardness and regenerating the ion-exchange bed is: first, passing hard water into the column; second, exchanging calcium and magnesium ions for sodium ions; third, collecting the softened water; and fourth, regenerating the exhausted column with concentrated brine.
Hard water softening via the permutit process begins by feeding water containing hardness-causing cations (Ca2+\text{Ca}^{2+}, Mg2+\text{Mg}^{2+}) into the zeolite column. As the water percolates, an ion exchange occurs where Ca2+\text{Ca}^{2+} and Mg2+\text{Mg}^{2+} bind to the matrix while Na+\text{Na}^+ is released. The softened water free of calcium and magnesium is then collected. Finally, once the column becomes exhausted, a concentrated brine solution (NaCl\text{NaCl}) is flushed through to regenerate the zeolite bed for repeated use.

Step-by-Step Solution

1
Introduce hard water containing calcium and magnesium ions into the column.
Untreated water makes contact with the active sodium zeolite matrix.
Ion exchange requires direct contact between the dissolved divalent metal ions and the exchanger bed.
2
Execute the cation exchange reaction.
Calcium and magnesium ions bind to the zeolite structure, releasing sodium ions into solution.
Sodium zeolite (Na2Z\text{Na}_2\text{Z}) trades its Na+\text{Na}^+ ions for Ca2+\text{Ca}^{2+} or Mg2+\text{Mg}^{2+} due to structural affinity.
3
Collect the effluent water.
Water free of Ca2+\text{Ca}^{2+} and Mg2+\text{Mg}^{2+} ions is obtained.
Sodium salts left in solution do not react with soap to form scum or cause scale build-up.
4
Regenerate the exhausted exchanger with concentrated sodium chloride (brine).
The column is converted back to active sodium zeolite (Na2Z\text{Na}_2\text{Z}).
High concentration of Na+\text{Na}^+ ions forces the reverse reaction, removing bound Ca2+\text{Ca}^{2+} and Mg2+\text{Mg}^{2+} ions.

Key Concept

Ion-Exchange Softening and Permutit Regeneration
Question 239Question →

A commercial distributor operates as a vital intermediary between industrial manufacturers and retail shops. Arrange the following operational functions of a merchant wholesaler in the correct chronological sequence, from initial bulk procurement down to final delivery to retailers.

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Answer

The correct sequence of wholesale operations is: purchasing finished merchandise in bulk from producers, storing stock in central warehouses, sorting and breaking bulk into smaller standardized packages, and finally selling smaller lots to retail shops on credit terms.
The operational flow of wholesale trade begins with bulk purchasing directly from industrial manufacturers. The inventory is then moved into central warehouses for storage. Inside the warehouse, the wholesaler performs bulk breaking, grading, and repackaging into smaller lots. Finally, these smaller packages are sold and dispatched to retail traders, frequently accompanied by commercial credit facilities.

Step-by-Step Solution

1
Identify the initial supply chain entry point
Purchasing in bulk directly from producers is the starting point of the wholesale trade process.
Wholesalers must first acquire title and possession of manufactured goods before performing internal handling.
2
Determine the immediate post-procurement storage function
Storing stock in central warehousing follows bulk purchasing.
Holding stock buffers against price volatility and ensures continuity of market supply.
3
Identify the primary value-addition processing stage
Sorting, grading, and breaking bulk into smaller packages occurs while goods are held in inventory.
Retailers cannot purchase factory bulk units, so the wholesaler must repackage items into smaller quantities.
4
Establish the final distribution stage to retail outlets
Selling and dispatching smaller lots to retail shops on credit terms completes the wholesale operational sequence.
This places the products into the retail trade channel for ultimate sale to consumers.

Key Concept

Sequential Functions of Merchant Wholesalers in Distribution Channels
Question 240Question →

Sequence the evolutionary stages of exchange media in Commerce, ordering them from the earliest historical form of money to the most modern development.

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Answer

The correct historical sequence from earliest to most modern form of money is: Commodity Money → Metallic Money → Paper Currency → Electronic Money.
Money evolved chronologically in response to commercial needs: first came Commodity Money (useful physical goods), followed by Metallic Money (durable minted coins), then Paper Currency (convenient representation of stored value), and finally Electronic Money (cashless digital balances).

Step-by-Step Solution

1
Identify the earliest exchange medium
Commodity money (cowries, cattle) was used immediately following the collapse/limitations of trade by barter.
Intrinsic value and direct utility made raw commodities the initial universal medium.
2
Determine the second historical phase
Metallic money (precious metal coins) replaced bulky and perishable commodities.
Metals like gold and silver offered durability, uniformity, and easy divisibility.
3
Determine the third historical phase
Paper currency developed as goldsmith receipts gained widespread acceptance in commerce.
Carrying heavy coins was risky, leading traders to use paper receipts which eventually became state fiat money.
4
Identify the latest monetary innovation
Electronic money emerged with modern computing infrastructure.
Digital balances and card-based transactions allow cashless commerce without physical banknotes.

Key Concept

Historical Evolution of Forms of Money
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