For each of these Lewis symbols, indicate the group in the periodic table in which the element X belongs: (a)

Illustrated are four ions — A, B, X, and Y— showing their relative ionic radii. The ions shown in red carry positive charges: a 2+ charge for A and a 1+ charge for B. Ions shown in blue carry negative charges: a 1- charge for X and a 2- charge for Y. (b) Among the combinations in part (a), which leads to the ionic compound having the largest lattice energy?

A portion of a two-dimensional 'slab' of NaCl(s) is shown here (see Figure 8.2) in which the ions are numbered. (a) Which colored balls must represent sodium ions?

A portion of a two-dimensional 'slab' of NaCl(s) is shown here (see Figure 8.2) in which the ions are numbered. (d) Consider ion 5. How many repulsive interactions are shown for it?

The orbital diagram that follows shows the valence electrons for a 2+ ion of an element. (a) What is the element?

In the Lewis structure shown here, A, D, E, Q, X, and Z represent elements in the first two rows of the periodic table. Identify all six elements so that the formal charges of all atoms are zero.

The partial Lewis structure that follows is for a hydrocarbon molecule. In the full Lewis structure, each carbon atom satisfies the octet rule, and there are no unshared electron pairs in the molecule. The carbon—carbon bonds are labeled 1, 2, and 3. (a) How many hydrogen atoms are in the molecule?

The partial Lewis structure that follows is for a hydrocarbon molecule. In the full Lewis structure, each carbon atom satisfies the octet rule, and there are no unshared electron pairs in the molecule. The carbon—carbon bonds are labeled 1, 2, and 3. (c) Which carbon—carbon bond is the strongest one?

Consider the Lewis structure for the polyatomic oxyanion shown here, where X is an element from the third period (Na - Ar). By changing the overall charge, n, from 1- to 2- to 3- we get three different polyatomic ions. For each of these ions (b) determine the formal charge of the central atom, X;

(a) True or false: An element's number of valence electrons is the same as its atomic number.

(b) How many valence electrons does a nitrogen atom possess?

(c) An atom has the electron configuration 1s²2s²2p⁶3s²3p². How many valence electrons does the atom have?

(a) True or false: The hydrogen atom is most stable when it has a full octet of electrons.

Ammonium chloride, NH₄Cl, is a very soluble salt in water. (b) Is there an N—Cl bond in solid ammonium chloride?

Consider the element silicon, Si. (c) Which subshells hold the valence electrons?

(a) Write the electron configuration for the element titanium, Ti. How many valence electrons does this atom possess?

(b) Hafnium, Hf, is also found in group 4. Write the electron configuration for Hf.

(c) Ti and Hf behave as though they possess the same number of valence electrons. Which of the subshells in the electron configuration of Hf behave as valence orbitals? Which behave as core orbitals?

Write the Lewis symbol for atoms of each of the following elements: (a) Te (b) Si (c) Ar (d) P

What is the Lewis symbol for each of the following atoms or ions? (a) Be (b) Rb

What is the Lewis symbol for each of the following atoms or ions? (c) Sn²⁺

(a) Using Lewis symbols, make a sketch of the reaction between magnesium and oxygen atoms to give the ionic substance MgO

Predict the chemical formula of the ionic compound formed between the following pairs of elements: (a) Al and Cl

Predict the chemical formula of the ionic compound formed between the following pairs of elements: (b) Mg and O (c) Zn and Cl

Predict the chemical formula of the ionic compound formed between the following pairs of elements: (d) Li and O.

Which ionic compound is expected to form from combining the following pairs of elements? (a) calcium and nitrogen (b) cesium and bromine (c) strontium and sulfur

Which ionic compound is expected to form from combining the following pairs of elements? (d) aluminum and selenium.