Atomic Structure and Chemical Bonding

Magnesium oxide ($MgO$) has a significantly higher melting point than sodium chloride ($NaCl$) because the electrostatic forces of attraction between its divalent ions ($Mg^{2+}$ and $O^{2-}$) are substantially stronger than those between the monovalent ions ($Na^+$ and $Cl^-$).

Which of the following chemical species contains both covalent and dative (coordinate) covalent bonds?

Match each chemical species in Column A with its correct bonding description in Column B.

Element $Y$ exists naturally as two isotopes, $^{63}Y$ and $^{65}Y$. If the relative atomic mass of element $Y$ is $63.5$, what is the percentage abundance of the lighter isotope, $^{63}Y$?

A tripositive ion, $X^{3+}$, has a mass number of $56$ and contains $23$ electrons. How many neutrons are present in the nucleus of an atom of element $X$?

Complete the statement below regarding the chemical reaction between ammonia and boron trifluoride.

A sulfide ion is represented by the symbol $^{32}_{16}\text{S}^{2-}$. How many neutrons, protons, and electrons are present in this ion?

An atom of potassium is represented by the nuclide symbol $^{39}_{19}\text{K}$. How many neutrons are present in the nucleus of this atom?

Element $X$ exists naturally as three isotopes with mass numbers $24$, $25$, and $26$. The relative atomic mass of element $X$ is $24.32$. If the natural abundance of the isotope $^{25}X$ is $10\%$, what is the percentage abundance of the isotope $^{26}X$?

Element $M$ has a relative atomic mass of $24.32$. It exists naturally as three isotopes: $^{24}M$ with a relative abundance of $79\%$, $^{25}M$ with a relative abundance of $10\%$, and an isotope $^{x}M$ with a relative abundance of $11\%$. What is the mass number ($x$) of the third isotope?

Match each quantum rule or principle with its correct statement regarding electronic configuration.

In the carbon monoxide molecule ($CO$), a triple covalent linkage holds the carbon and oxygen atoms together. Which statement correctly describes the nature of the bonding pairs between the two atoms and identifies the electron pair donor for the dative (coordinate) bond?

An element $M$ forms a stable electrovalent chloride with the formula $MCl_2$. If the dipositive cation $M^{2+}$ has the electronic configuration $1s^2 2s^2 2p^6 3s^2 3p^6$, which of the following statements correctly explains the electrical conductivity and lattice properties of $MCl_2$?

Consider three Period 3 elements: sodium ($Na$), magnesium ($Mg$), and aluminium ($Al$). As one moves from $Na$ to $Al$ across the period, there is a notable increase in both melting point and electrical conductivity per mole of metal. Which of the following best accounts for this observed trend in metallic bond strength and physical properties?

Match each microscopic structural feature of metallic bonding on the left with the macroscopic physical property of metals on the right that directly results from it.

Complete the statement below regarding chemical bonding.

Which of the following best explains why solid sodium chloride ($NaCl$) does not conduct electricity, whereas molten sodium chloride conducts electricity readily?

Magnesium oxide ($MgO$) has a significantly higher melting point ($2,852^\circ\text{C}$) than sodium fluoride ($NaF$) ($996^\circ\text{C}$) primarily because the product of the ionic charges in $MgO$ is four times greater than in $NaF$, resulting in stronger electrostatic forces within the crystal lattice. Is this statement true or false?

Match each physical property of metallic elements listed on the left with the atomic-scale mechanism on the right that best accounts for it.

Complete the following statement describing the bonding and structural change during the dimerization of aluminium chloride.