Tüm alıştırma soruları

13931 soru

Soru 6821Soru

Chief Kalu insured his commercial supermarket building, valued at N50,000,000\text{N}50,000,000, against fire for a sum of N35,000,000\text{N}35,000,000. The policy contains an average clause. If a fire outbreak damages the building causing a loss of N10,000,000\text{N}10,000,000, what amount in Naira will the insurance company pay as indemnity?

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Cevap: 7000000

Cevap

7,000,000 Naira
Under the average clause in fire insurance policies, if a property is under-insured (insured for less than its true value), the insured is deemed to be their own insurer for the uninsured portion. Here, the building was insured for 70% of its full value (N35,000,000 / N50,000,000 = 0.70). Therefore, the insurance company pays only 70% of the actual loss incurred (70% of N10,000,000 = 7,000,000 Naira).

Adım Adım Çözüm

1
Identify the property values given in the problem statement.
Actual Value = N50,000,000; Sum Insured = N35,000,000; Actual Loss = N10,000,000.
These figures are required to calculate indemnity under under-insurance.
2
Apply the average clause compensation formula.
Compensation = (Sum Insured / Actual Value) * Actual Loss
When property is insured for less than its full value and has an average clause, the insurer pays only a proportionate share of any loss.
3
Calculate the compensation payable.
Compensation = (35,000,000 / 50,000,000) * 10,000,000 = 7,000,000 Naira.
Since the owner insured 70% of the building's value, the insurer pays 70% of the actual loss suffered.

Anahtar Kavram

Average Clause in Insurance
Soru 6822Soru

Complete the statement below by calculating the missing pOH and pH values for the given alkaline solution.

Aşağıdaki boşlukları doldurun

A solution of potassium hydroxide (KOH\text{KOH}) has a hydroxide ion concentration of 0.01 mol dm30.01\text{ mol dm}^{-3} at 25C25^\circ\text{C}. The pOH of this solution is and its pH is .
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Cevap

The pOH of the potassium hydroxide solution is 2 and its pH is 12.
Potassium hydroxide (KOH\text{KOH}) dissociates completely in water to yield a hydroxide ion concentration of [OH]=1.0×102 mol dm3[\text{OH}^-] = 1.0 \times 10^{-2}\text{ mol dm}^{-3}. The pOH is calculated as log10(102)=2-\log_{10}(10^{-2}) = 2. Since pH+pOH=14\text{pH} + \text{pOH} = 14 at 25C25^\circ\text{C}, subtracting 2 from 14 gives a pH of 12.

Adım Adım Çözüm

1
Calculate the pOH from the given hydroxide ion concentration [OH][\text{OH}^-].
pOH=log10(0.01)=log10(102)=2\text{pOH} = -\log_{10}(0.01) = -\log_{10}(10^{-2}) = 2
KOH\text{KOH} is a strong monobasic base that fully dissociates in water, giving [OH]=0.01 mol dm3[\text{OH}^-] = 0.01\text{ mol dm}^{-3}.
2
Calculate the pH using the relationship pH+pOH=14\text{pH} + \text{pOH} = 14 at 25C25^\circ\text{C}.
pH=14pOH=142=12\text{pH} = 14 - \text{pOH} = 14 - 2 = 12
The sum of pH and pOH for any aqueous solution at standard temperature (25C25^\circ\text{C}) equals 14.

Anahtar Kavram

Determination of pOH and pH for strong base solutions using the ion product constant of water.
Tahmini Süre:1m 0s
Soru 6823Soru

Which commercial banking payment service is described in the statement below?

Aşağıdaki boşlukları doldurun

An arrangement where a business owner authorizes their bank to allow a creditor to collect variable amounts of money directly from the business account at agreed intervals is known as a .
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Cevap

Direct debit
Direct debit is the commercial banking service that enables a creditor, with prior consent from the account holder, to pull variable sums of money directly from the debtor's account.

Adım Adım Çözüm

1
Analyze the operational features of the payment system described.
The payment arrangement allows a third party (the creditor) to initiate collection of varying amounts from the debtor's account after obtaining prior authorization.
Differentiating banking services relies on knowing who initiates the payment request and whether the payment amount is fixed or variable.
2
Compare direct debits with other bank transfer methods such as standing orders.
A standing order is initiated by the account holder for fixed amounts, whereas a direct debit is initiated by the creditor for variable or recurring amounts.
Business traders use direct debits for fluctuating settlement needs such as variable utility bills or inventory purchases.

Anahtar Kavram

A direct debit is an authorization given by an account holder to a commercial bank, empowering a named creditor to claim variable payments directly from the account at specified intervals.
Tahmini Süre:1m 0s
Soru 6824Soru

A sealed rigid reaction flask contains a sample of argon gas at a pressure of 120 kPa120\text{ kPa} when the temperature is 30C30^\circ\text{C}. If the flask is heated to a temperature of 333C333^\circ\text{C} while maintaining a constant volume, what is the final pressure of the gas?

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Cevap: 240 kPa240\text{ kPa}

Cevap

The final pressure of the gas is 240 kPa240\text{ kPa}.
According to the Pressure Law (Gay-Lussac's Law), the pressure of a fixed mass of gas is directly proportional to its absolute temperature when volume remains constant (P1/T1=P2/T2P_1/T_1 = P_2/T_2). Converting temperatures to Kelvin yields T1=30+273=303 KT_1 = 30 + 273 = 303\text{ K} and T2=333+273=606 KT_2 = 333 + 273 = 606\text{ K}. Substituting these into P2=120×(606/303)P_2 = 120 \times (606 / 303) gives 240 kPa240\text{ kPa}.

Adım Adım Çözüm

1
Convert given temperatures from Celsius to Kelvin.
T1=30+273=303 KT_1 = 30 + 273 = 303\text{ K} and T2=333+273=606 KT_2 = 333 + 273 = 606\text{ K}.
Gas law equations require absolute temperature measured on the Kelvin scale.
2
State the Pressure Law formula relating initial and final values at constant volume.
P1T1=P2T2    P2=P1×T2T1\frac{P_1}{T_1} = \frac{P_2}{T_2} \implies P_2 = P_1 \times \frac{T_2}{T_1}.
At constant volume, the pressure of a fixed mass of gas is directly proportional to its absolute temperature.
3
Substitute the values into the equation to calculate final pressure P2P_2.
P2=120 kPa×606 K303 K=120 kPa×2=240 kPaP_2 = 120\text{ kPa} \times \frac{606\text{ K}}{303\text{ K}} = 120\text{ kPa} \times 2 = 240\text{ kPa}.
Since absolute temperature doubles from 303 K303\text{ K} to 606 K606\text{ K}, the pressure must also double.

Anahtar Kavram

Pressure Law (Gay-Lussac's Law)
Soru 6825Soru

At a magnetic observation station, the horizontal component of the Earth's magnetic field is 40 μT40\text{ }\mu\text{T} and the vertical component is 30 μT30\text{ }\mu\text{T}. What is the total magnetic field intensity of the Earth at this station in μT\mu\text{T}?

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Cevap: 50

Cevap

The total magnetic field intensity of the Earth at this station is 50 μT50\text{ }\mu\text{T}.
The horizontal component (BhB_h) and vertical component (BvB_v) of the Earth's magnetic field act at right angles to each other. Therefore, the resultant total magnetic field intensity (BB) is calculated using vector addition: B=Bh2+Bv2=402+302=50 μTB = \sqrt{B_h^2 + B_v^2} = \sqrt{40^2 + 30^2} = 50\text{ }\mu\text{T}.

Adım Adım Çözüm

1
Identify the vector relationship between the horizontal and vertical components of the Earth's magnetic field.
B=Bh2+Bv2B = \sqrt{B_h^2 + B_v^2}, where Bh=40 μTB_h = 40\text{ }\mu\text{T} and Bv=30 μTB_v = 30\text{ }\mu\text{T}.
The horizontal and vertical components of the Earth's magnetic field are mutually perpendicular vector components.
2
Substitute the values into the formula and solve for total magnetic field intensity BB.
B=(40)2+(30)2=1600+900=2500=50 μTB = \sqrt{(40)^2 + (30)^2} = \sqrt{1600 + 900} = \sqrt{2500} = 50\text{ }\mu\text{T}.
Applying the Pythagorean theorem yields the magnitude of the resultant magnetic field vector.

Anahtar Kavram

Resolution of Earth's magnetic field into horizontal (BhB_h) and vertical (BvB_v) components.
Tahmini Süre:1m 0s
Soru 6826Soru

A central bank issues a new currency series printed with precise physical specifications, ensuring that every note of a given denomination has identical appearance, weight, and value. Which characteristic of money does this standardized production primarily maintain?

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Cevap: Homogeneity

Cevap

Homogeneity is the characteristic that guarantees every unit of money within a particular denomination is uniform and indistinguishable from another of equal face value.
Homogeneity (or uniformity) requires that every unit of currency within the same denomination must be identical in form, design, and purchasing power so that no unit is preferred over another of the same face value.

Adım Adım Çözüm

1
Analyze the core requirement in the stem
The stem describes producing banknotes of equal denomination that are completely identical in size, appearance, and value.
Identifying the key attribute being described helps isolate the exact characteristic of money.
2
Evaluate the definition of homogeneity in economics
Homogeneity (or uniformity) dictates that all units of a particular denomination must be standard so traders treat them as identical substitutes.
This prevents discrimination between individual notes of the same face value.

Anahtar Kavram

Homogeneity as a key characteristic of money
Soru 6827Soru

A merchant insured his shop inventory strictly against loss caused by fire. Subsequently, a heavy flood submerged the warehouse and damaged the inventory, but no fire occurred. The insurance company denied the merchant's claim for compensation. Which principle of insurance supports the insurer's decision?

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Cevap: Proximate cause

Cevap

Proximate cause
Under the principle of proximate cause (causa proxima), an insurer is obligated to pay compensation only when the direct, immediate, and dominant cause of the loss is the specific risk insured against. Because the inventory was damaged by flooding (an uninsured peril) rather than fire (the insured peril), the insurer is legally justified in rejecting the claim.

Adım Adım Çözüm

1
Identify the insured peril and the actual cause of damage
The insured peril was fire, whereas the actual cause of loss was flooding.
To determine policy coverage, the active event leading to the damage must be identified.
2
Apply the relevant insurance principle to the facts
The principle of proximate cause (causa proxima) dictates that compensation is only payable if the direct and effective cause of loss is the peril insured against.
Because flooding was not included in the fire policy, the loss falls outside the insurer's liability.

Anahtar Kavram

Principle of Proximate Cause (Causa Proxima)
Soru 6828Soru

Match each money characteristic or function on the left with its corresponding operational description on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Portability
Divisibility
Standard of deferred payment
Store of value

Eşleşmeler

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Cevap

Portability matches with allowing purchasing power to be carried around conveniently; Divisibility matches with facilitating transactions of small and varying denominations; Standard of deferred payment matches with providing an agreed unit for settling future credit obligations; Store of value matches with enabling income to be saved and preserved for future consumption.
Each feature of money uniquely satisfies a distinct commercial need: portability enables physical ease of carrying currency; divisibility permits payments of various exact sizes; standard of deferred payment facilitates credit and deferred settlements; and store of value allows saving purchasing power for future periods.

Adım Adım Çözüm

1
Analyze physical characteristics of money (left_1 and left_2)
Portability guarantees ease of mobility (right_2), while divisibility allows money to exist in fractional units for exact change (right_1).
Physical characteristics determine how convenient money is to handle in everyday commercial exchanges.
2
Analyze secondary functions of money (left_3 and left_4)
Standard of deferred payment serves future debt settlements (right_4), while store of value enables wealth accumulation over time (right_3).
Secondary functions support economic planning, credit structures, and capital accumulation.

Anahtar Kavram

Functions and Characteristics of Money
Soru 6829Soru

A solution is prepared by dissolving 0.04 g0.04\text{ g} of sodium hydroxide (NaOH\text{NaOH}) in distilled water to make 1.0 dm31.0\text{ dm}^3 of solution at 25C25^\circ\text{C}. What is the pH\text{pH} of the resulting solution? [Molar mass of NaOH=40 g mol1\text{NaOH} = 40\text{ g mol}^{-1}]

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Cevap: 11.011.0

Cevap

The pH of the resulting solution is 11.011.0.
The solution contains 0.04 g0.04\text{ g} of NaOH\text{NaOH} in 1.0 dm31.0\text{ dm}^3, which corresponds to 0.001 mol dm30.001\text{ mol dm}^{-3} or 1.0×103 mol dm31.0 \times 10^{-3}\text{ mol dm}^{-3}. Since NaOH\text{NaOH} is a strong base, [OH]=1.0×103 mol dm3[\text{OH}^-] = 1.0 \times 10^{-3}\text{ mol dm}^{-3}, giving a pOH\text{pOH} of 3.03.0. Using the relationship pH+pOH=14\text{pH} + \text{pOH} = 14, the pH\text{pH} is 14.03.0=11.014.0 - 3.0 = 11.0.

Adım Adım Çözüm

1
Calculate the molar concentration of sodium hydroxide (NaOH\text{NaOH}).
Molar concentration=0.04 g dm340 g mol1=0.001 mol dm3=1.0×103 mol dm3\text{Molar concentration} = \frac{0.04\text{ g dm}^{-3}}{40\text{ g mol}^{-1}} = 0.001\text{ mol dm}^{-3} = 1.0 \times 10^{-3}\text{ mol dm}^{-3}.
Concentration must be in mol dm3\text{mol dm}^{-3} before calculating ion concentration and pOH\text{pOH}.
2
Determine the hydroxide ion concentration [OH][\text{OH}^-].
[OH]=1.0×103 mol dm3[\text{OH}^-] = 1.0 \times 10^{-3}\text{ mol dm}^{-3}.
NaOH\text{NaOH} is a strong monobasic base that completely dissociates into Na+\text{Na}^+ and OH\text{OH}^- ions.
3
Calculate the pOH\text{pOH} of the solution.
pOH=log10[OH]=log10(1.0×103)=3.0\text{pOH} = -\log_{10}[\text{OH}^-] = -\log_{10}(1.0 \times 10^{-3}) = 3.0.
pOH\text{pOH} is defined as the negative base-10 logarithm of the hydroxide ion concentration.
4
Convert pOH\text{pOH} to pH\text{pH}.
pH=14.0pOH=14.03.0=11.0\text{pH} = 14.0 - \text{pOH} = 14.0 - 3.0 = 11.0.
At 25C25^\circ\text{C}, pH+pOH=14.0\text{pH} + \text{pOH} = 14.0.

Anahtar Kavram

Calculating pH from the mass concentration of a strong base via pOH conversion
Tahmini Süre:1m 30s
Soru 6830Soru

A fixed mass of an ideal gas occupies a volume of 3.0 dm33.0\text{ dm}^3 at 27C27^\circ\text{C} and a pressure of 1.0 atm1.0\text{ atm}. What is the final volume of the gas in dm3\text{dm}^3 when the temperature is increased to 127C127^\circ\text{C} while maintaining constant pressure?

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Cevap: 4.0; 4; 4.0 dm3; 4 dm3; 4.0 dm³; 4 dm³

Cevap

The final volume of the gas is 4.0 dm34.0\text{ dm}^3.
First convert temperatures to Kelvin: T1=27+273=300 KT_1 = 27 + 273 = 300\text{ K} and T2=127+273=400 KT_2 = 127 + 273 = 400\text{ K}. At constant pressure, V1T1=V2T2\frac{V_1}{T_1} = \frac{V_2}{T_2}. Rearranging to solve for V2V_2 gives V2=3.0×400300=4.0 dm3V_2 = \frac{3.0 \times 400}{300} = 4.0\text{ dm}^3.

Adım Adım Çözüm

1
Convert both temperatures from degrees Celsius to Kelvin
T1=27+273=300 KT_1 = 27 + 273 = 300\text{ K} and T2=127+273=400 KT_2 = 127 + 273 = 400\text{ K}
Gas law calculations strictly require absolute temperature measured in Kelvin.
2
Apply Charles's Law derived from the ideal gas equation (PV=nRTPV = nRT) at constant pressure
V1T1=V2T2\frac{V_1}{T_1} = \frac{V_2}{T_2}
Volume is directly proportional to absolute temperature when pressure and amount of gas are constant.
3
Substitute the values into the formula and solve for V2V_2
V_2 = \frac{V_1 \times T_2}{T_1} = \frac{3.0 \times 400}{300} = 4.0\text{ dm}^3
Calculates the new gas volume.

Anahtar Kavram

General Gas Law and Absolute Temperature Conversion
Soru 6831Soru

A trader holds Treasury bills, bills of exchange, and savings bank deposits. Although these assets serve as a reliable store of value and can easily be converted into cash, they cannot be spent directly as a medium of exchange to purchase goods. Under which form of money are these financial assets classified?

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Cevap: Near money

Cevap

Near money
Near money (or quasi-money) refers to highly liquid assets such as Treasury bills, bills of exchange, and savings deposits. They perform the store of value function of money and can quickly be turned into cash, but cannot be used directly as a medium of exchange for purchasing goods.

Adım Adım Çözüm

1
Examine the properties of the financial assets listed in the stem (Treasury bills, bills of exchange, savings deposits).
These assets possess high liquidity and act as a store of wealth, but cannot be used directly to pay for goods in everyday transactions.
Forms of money are categorized by their liquidity level and their ability to serve directly as a medium of exchange.
2
Match these properties against the standard definitions of forms of money in Commerce.
Assets that must be converted into cash or bank deposits before spending are categorized as near money or quasi-money.
Near money acts as a close substitute for money without having immediate medium-of-exchange status.

Anahtar Kavram

Types and Forms of Money - Near Money (Quasi-Money)
Soru 6832Soru

A chemist needs to prepare a pure, hydrated sample of copper(II) tetraoxosulfate(VI) (CuSO45H2OCuSO_4 \cdot 5H_2O) starting from insoluble copper(II) oxide (CuOCuO). Which of the following experimental procedures is correct for this preparation?

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Cevap: Add excess copper(II) oxide to dilute tetraoxosulfate(VI) acid, filter the mixture, concentrate the filtrate, and allow it to cool for crystallization.

Cevap

The correct procedure is to react excess insoluble copper(II) oxide with dilute tetraoxosulfate(VI) acid, filter out the unreacted solid, concentrate the filtrate by gentle heating, and cool to form crystals.
The standard method for preparing a soluble salt from an insoluble oxide involves adding excess oxide to hot dilute acid to ensure complete acid neutralization, filtering out the unreacted solid, and partially evaporating the filtrate so that hydrated crystals form upon cooling.

Adım Adım Çözüm

1
Identify the solubility of the product salt and reactants
Copper(II) tetraoxosulfate(VI) (CuSO4CuSO_4) is a soluble salt, while copper(II) oxide (CuOCuO) is an insoluble base.
Soluble salts prepared from insoluble bases require the excess insoluble reactant method.
2
Neutralize dilute acid with excess insoluble base
Warm H2SO4(aq)H_2SO_4(aq) reacts with excess CuO(s)CuO(s) according to: CuO(s)+H2SO4(aq)CuSO4(aq)+H2O(l)CuO(s) + H_2SO_4(aq) \rightarrow CuSO_4(aq) + H_2O(l).
Using excess base ensures all acid is fully consumed.
3
Separate unreacted solid and crystallize
Filter off unreacted CuOCuO, heat the filtrate to crystallizing point, and cool slowy to obtain hydrated crystals (CuSO45H2OCuSO_4 \cdot 5H_2O).
Filtration removes insoluble excess, and gentle cooling preserves water of crystallization.

Anahtar Kavram

Preparation of soluble salts using dilute acids and insoluble bases
Tahmini Süre:1m 30s
Soru 6833Soru

A rigid container holds a gas mixture containing 4.0 g4.0\text{ g} of methane (CH4\text{CH}_4) and 14.0 g14.0\text{ g} of nitrogen (N2\text{N}_2). If the partial pressure exerted by methane in the mixture is 125 kPa125\text{ kPa}, what is the total pressure of the gas mixture in kPa\text{kPa}? [Relative atomic masses: H=1\text{H} = 1, C=12\text{C} = 12, N=14\text{N} = 14]

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Cevap: 375

Cevap

The total pressure of the gas mixture is 375 kPa375\text{ kPa}.
The total pressure of 375 kPa375\text{ kPa} is determined by calculating the moles of methane (0.25 mol0.25\text{ mol}) and nitrogen (0.50 mol0.50\text{ mol}), giving a total of 0.75 mol0.75\text{ mol}. Methane constitutes one-third (1/31/3) of the total moles, so its partial pressure is one-third of the total pressure. Dividing the partial pressure of methane (125 kPa125\text{ kPa}) by its mole fraction (1/31/3) yields a total pressure of 375 kPa375\text{ kPa}.

Adım Adım Çözüm

1
Calculate the amount of moles of each gas present in the mixture.
nCH4=4.0 g16 g/mol=0.25 moln_{\text{CH}_4} = \frac{4.0\text{ g}}{16\text{ g/mol}} = 0.25\text{ mol} and nN2=14.0 g28 g/mol=0.50 moln_{\text{N}_2} = \frac{14.0\text{ g}}{28\text{ g/mol}} = 0.50\text{ mol}.
Molar masses are determined from relative atomic masses: CH4=12+4(1)=16 g/mol\text{CH}_4 = 12 + 4(1) = 16\text{ g/mol} and N2=2(14)=28 g/mol\text{N}_2 = 2(14) = 28\text{ g/mol}.
2
Calculate total moles and the mole fraction of methane.
ntotal=0.25+0.50=0.75 moln_{\text{total}} = 0.25 + 0.50 = 0.75\text{ mol}; XCH4=0.25 mol0.75 mol=13X_{\text{CH}_4} = \frac{0.25\text{ mol}}{0.75\text{ mol}} = \frac{1}{3}.
Mole fraction is the ratio of the number of moles of a specific gas component to the total number of moles in the gas mixture.
3
Apply Dalton's Law of Partial Pressures to find total pressure.
Ptotal=PCH4XCH4=125 kPa1/3=375 kPaP_{\text{total}} = \frac{P_{\text{CH}_4}}{X_{\text{CH}_4}} = \frac{125\text{ kPa}}{1/3} = 375\text{ kPa}.
According to Dalton's Law, the partial pressure of a gas is equal to its mole fraction multiplied by the total pressure (Pi=Xi×PtotalP_i = X_i \times P_{\text{total}}).

Anahtar Kavram

Dalton's Law of Partial Pressures and Mole Fraction
Tahmini Süre:1m 30s
Soru 6834Soru

What is the ground-state electronic configuration of the chromium(III) ion, Cr3+Cr^{3+}? (Atomic number of Cr=24Cr = 24)

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Cevap: 1s22s22p63s23p63d31s^2 2s^2 2p^6 3s^2 3p^6 3d^3

Cevap

1s22s22p63s23p63d31s^2 2s^2 2p^6 3s^2 3p^6 3d^3
Neutral chromium (Z=24Z = 24) has the ground-state electron configuration 1s22s22p63s23p63d54s11s^2 2s^2 2p^6 3s^2 3p^6 3d^5 4s^1. When forming the Cr3+Cr^{3+} ion, three electrons must be removed. Outer shell (4s4s) electrons are lost first, followed by (n1)d(n-1)d electrons. Removing one electron from 4s4s and two from 3d3d gives the configuration 1s22s22p63s23p63d31s^2 2s^2 2p^6 3s^2 3p^6 3d^3.

Adım Adım Çözüm

1
Determine the electronic configuration of neutral chromium (CrCr)
Ground state CrCr (Z=24Z = 24) is 1s22s22p63s23p63d54s11s^2 2s^2 2p^6 3s^2 3p^6 3d^5 4s^1
Chromium exhibits an anomalous configuration due to the extra stability of a half-filled 3d3d subshell.
2
Apply the rule for cation formation in transition metals
Electrons in the outermost shell (n=4n=4, 4s4s subshell) are lost before electrons in the inner subshell (n=3n=3, 3d3d subshell).
The 4s4s electrons experience lower effective nuclear attraction in the ionized state and are situated at a higher principal energy level.
3
Remove 3 electrons to form Cr3+Cr^{3+}
Remove 1 electron from 4s4s and 2 electrons from 3d3d: (3d54s1)3e=3d34s0(3d^5 4s^1) - 3e^- = 3d^3 4s^0
Removing 1 electron from 4s4s leaves 3d53d^5; removing two more from 3d3d leaves 3d33d^3.

Anahtar Kavram

Electronic configuration of d-block transition metal cations
Tahmini Süre:1m 0s
Soru 6835Soru

Match each mode of transport or specialized logistical system on the left with its primary operational feature or commercial function in trade on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Pipeline Transport
Containerization
Tramp Steamer Shipping
Inland Waterway Barges

Eşleşmeler

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Cevap

Pipeline Transport matches continuous automated fluid movement; Containerization matches standardized intermodal unit loads; Tramp Steamer Shipping matches unscheduled ocean charters for bulk cargo; Inland Waterway Barges match low-cost river and canal transport for heavy bulk goods.
Each mode of transport is uniquely suited to specific cargo types and operational conditions. Pipeline transport provides automated, continuous flow for liquids and gases; containerization standardizes unit loading across different transit modes; tramp steamers offer flexible unscheduled bulk ocean carriage; and inland waterway barges afford economical bulk movement along navigable waterways.

Adım Adım Çözüm

1
Analyze the operational characteristics of each transport mode and logistical system.
Identify that pipelines convey fluids continuously, containerization standardizes unit loading, tramp steamers operate on unscheduled charters, and inland barges carry heavy bulk goods along rivers.
Matching transport modes to commercial functions requires aligning technical capabilities with trade requirements.
2
Pair each term on the left with its unique matching function on the right.
Pipeline matches automated fluid conveyance; Containerization matches intermodal unit loading; Tramp Steamer matches unscheduled ocean charters; Inland Waterway Barges match low-cost river bulk transport.
Each mode serves distinct commercial needs regarding cargo type, flexibility, route fixing, and cost efficiency.

Anahtar Kavram

Modes of transportation and specialized logistics systems in commercial trade
Soru 6836Soru

Complete the following statement regarding laboratory methods of salt preparation and salt classification.

Aşağıdaki boşlukları doldurun

The preparation of anhydrous iron(III) chloride (FeCl3FeCl_3) by reacting red-hot iron filings directly with dry chlorine gas is an example of , whereas potash alum, KAl(SO4)212H2OKAl(SO_4)_2 \cdot 12H_2O, is classified as a salt.
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Cevap

The preparation method is direct combination (or synthesis), and potash alum is classified as a double salt.
Anhydrous binary salts like iron(III) chloride must be synthesized by direct combination of their elements in dry conditions to avoid hydrolysis. Potash alum is formed by equimolar crystallization of potassium sulfate and aluminium sulfate, yielding a double salt.

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1
Determine the preparation method for anhydrous iron(III) chloride.
Direct combination of elements (2Fe(s)+3Cl2(g)2FeCl3(s)2Fe_{(s)} + 3Cl_{2(g)} \rightarrow 2FeCl_{3(s)}) is used because aqueous crystallization causes salt hydrolysis.
Reacting two elements directly to form a compound without water is direct combination/synthesis.
2
Classify potash alum based on its chemical formula and ionic behavior.
Potash alum contains two distinct metallic cations (K+K^+ and Al3+Al^{3+}) combined with sulfate anions (SO42SO_4^{2-}), making it a double salt.
Salts composed of two simple salts crystallized together in equimolar proportions that dissociate completely into constituent ions are double salts.

Anahtar Kavram

Salt Preparation Methods and Classifications
Soru 6837Soru

A gas sample collected in a laboratory syringe occupies a volume of 600 cm3600\text{ cm}^3 at 27C27^\circ\text{C} and 1.0 atm1.0\text{ atm} pressure. What is the volume of the gas when the pressure is increased to 2.0 atm2.0\text{ atm} and the temperature is raised to 81C81^\circ\text{C}?

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Cevap: 354 cm3354\text{ cm}^3

Cevap

The final volume of the gas is 354 cm3354\text{ cm}^3.
Using the General Gas Law P1V1T1=P2V2T2\frac{P_1 V_1}{T_1} = \frac{P_2 V_2}{T_2} with absolute temperatures T1=300 KT_1 = 300\text{ K} (27C27^\circ\text{C}) and T2=354 KT_2 = 354\text{ K} (81C81^\circ\text{C}), the calculation yields V2=1.0×600×3542.0×300=354 cm3V_2 = \frac{1.0 \times 600 \times 354}{2.0 \times 300} = 354\text{ cm}^3.

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1
Convert temperatures from Celsius to Kelvin
T1=27+273=300 KT_1 = 27 + 273 = 300\text{ K} and T2=81+273=354 KT_2 = 81 + 273 = 354\text{ K}
Gas laws require absolute temperature values on the Kelvin scale.
2
Set up the General Gas Law equation
P1V1T1=P2V2T2    V2=P1V1T2P2T1\frac{P_1 V_1}{T_1} = \frac{P_2 V_2}{T_2} \implies V_2 = \frac{P_1 V_1 T_2}{P_2 T_1}
Pressure, volume, and temperature all change simultaneously for a fixed mass of gas.
3
Substitute the known values and calculate V2V_2
V2=1.0 atm×600 cm3×354 K2.0 atm×300 K=354 cm3V_2 = \frac{1.0\text{ atm} \times 600\text{ cm}^3 \times 354\text{ K}}{2.0\text{ atm} \times 300\text{ K}} = 354\text{ cm}^3
Simplifying 6002.0×300=1\frac{600}{2.0 \times 300} = 1 leaves 1×354=354 cm31 \times 354 = 354\text{ cm}^3.

Anahtar Kavram

General Gas Law (Combined Gas Law)
Tahmini Süre:1m 15s
Soru 6838Soru

At the Earth's magnetic poles, the horizontal component of the Earth's magnetic field reaches its maximum value while the vertical component is equal to zero.

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Cevap: False

Cevap

The statement is false. At the magnetic poles, the angle of dip is 9090^\circ, which means the horizontal component of the Earth's magnetic field is zero and the vertical component is at its maximum.
The statement is false because at the Earth's magnetic poles, the angle of inclination (dip) is 9090^\circ. Substituting this angle into the component resolution formulas yields Bh=Bcos90=0B_h = B \cos 90^\circ = 0 and Bv=Bsin90=BB_v = B \sin 90^\circ = B. Therefore, the horizontal component is zero and the vertical component is maximum at the poles.

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1
Determine the angle of dip (θ\theta) at the Earth's magnetic poles.
The angle of dip at the poles is θ=90\theta = 90^\circ.
The Earth's magnetic flux lines enter or leave the surface vertically at the magnetic poles.
2
Calculate the horizontal component (BhB_h) using the magnetic field resolution formula.
Bh=Bcos(90)=0B_h = B \cos(90^\circ) = 0.
Since cos(90)=0\cos(90^\circ) = 0, there is no horizontal magnetic field component at the poles.
3
Calculate the vertical component (BvB_v) using the magnetic field resolution formula.
Bv=Bsin(90)=BB_v = B \sin(90^\circ) = B.
Since sin(90)=1\sin(90^\circ) = 1, the vertical component accounts for the entire total magnetic field intensity.
4
Compare the calculated component values against the given statement.
The statement claims BhB_h is maximum and Bv=0B_v = 0, which contradicts the physical reality where Bh=0B_h = 0 and BvB_v is maximum.
Therefore, the statement is evaluated as false.

Anahtar Kavram

Earth's Magnetic Field Components at Magnetic Poles
Soru 6839Soru

A pharmaceutical firm based in Lagos needs to urgently dispatch a small, high-value consignment of temperature-sensitive vaccines to a health facility in Abuja within six hours. Which mode of transportation is most appropriate for moving this cargo?

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Cevap: Air transport

Cevap

Air transport is the most appropriate mode of transportation.
Air transport is the fastest mode of transportation in commerce. It is uniquely suited for high-value, light-weight, highly perishable, or time-critical shipments like vaccines, where speed and delicate handling outweigh higher freight charges.

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1
Analyze cargo characteristics and transit requirements
The shipment consists of high-value, low-weight, temperature-sensitive vaccines requiring emergency delivery across a long inland distance within six hours.
Mode selection in trade depends on speed, cost, safety, distance, and the physical characteristics of the cargo.
2
Evaluate transport options against constraints
Air transport is the only mode capable of fulfilling a strict six-hour transit window across long distances while ensuring maximum security for delicate cargo.
Rail and sea transport are too slow, and pipelines are restricted strictly to liquid/gas continuous bulk transfers.

Anahtar Kavram

Transportation mode selection based on speed, cargo perishability, value, and urgency
Tahmini Süre:1m 0s
Soru 6840Soru

The solubility of potassium trioxonitrate(V), KNO3\text{KNO}_3, in water at 40C40^\circ\text{C} is 6.0 mol dm36.0\text{ mol dm}^{-3}. What mass of KNO3\text{KNO}_3, in grams, is required to prepare a saturated solution in 250 cm3250\text{ cm}^3 of water at this temperature? (Molar mass of KNO3=101 g mol1\text{KNO}_3 = 101\text{ g mol}^{-1})

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Cevap: 151.5

Cevap

The mass of KNO3\text{KNO}_3 required to prepare a saturated solution in 250 cm3250\text{ cm}^3 of water at 40C40^\circ\text{C} is 151.5 g151.5\text{ g}.
To find the mass of solute required for saturation, convert the given volume of water to cubic decimeters (250 cm3=0.25 dm3250\text{ cm}^3 = 0.25\text{ dm}^3). Multiply the volume by the molar solubility (6.0 mol dm3×0.25 dm3=1.5 mol6.0\text{ mol dm}^{-3} \times 0.25\text{ dm}^3 = 1.5\text{ mol}) to obtain the number of moles, then multiply by the molar mass (1.5 mol×101 g mol1=151.5 g1.5\text{ mol} \times 101\text{ g mol}^{-1} = 151.5\text{ g}).

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1
Convert volume from cm3\text{cm}^3 to dm3\text{dm}^3
0.25 dm30.25\text{ dm}^3
Molar solubility is expressed per dm3\text{dm}^3, so the volume of solvent must be in dm3\text{dm}^3.
2
Determine moles of KNO3\text{KNO}_3 needed for saturation
1.5 mol1.5\text{ mol}
Multiply molar solubility by the volume in dm3\text{dm}^3.
3
Convert moles to mass in grams
151.5 g151.5\text{ g}
Multiply moles by the molar mass of KNO3\text{KNO}_3 (101 g mol1101\text{ g mol}^{-1}).

Anahtar Kavram

Calculating solute mass for saturation using molar solubility and volume
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