Question 1

An atom has 17 protons and 18 electrons. What is the correct symbol for this ion?

Accepted Answer

$$\mathrm{Cl}^{-}$$

Question 2

Which of the following is the correct formula for a compound formed between magnesium ions and nitrate ions?

Accepted Answer

$$\mathrm{Mg(NO_3$)_2}$$

Question 3

Which of the following is the correct formula for a compound containing aluminum ions and sulfate ions?

Accepted Answer

$$\mathrm{Al_2$(SO_4$)_3}$$

Question 4

Which of the following is a polyatomic anion?

Accepted Answer

$$\mathrm{SO_4$^{2-}}$$

Question 5

What is the correct name for the compound $$\mathrm{P_2O_5}$$?

Accepted Answer

Diphosphorus pentoxide

Question 6

How many valence electrons are present in a molecule of $$\mathrm{CO_2$}$$?

Accepted Answer

24

Question 7

Which of the following best describes the trend in electronegativity across a period in the periodic table?

Accepted Answer

Electronegativity increases from left to right.

Question 8

Given the following electronegativity values: $$\mathrm{H} = 2.1$$, $$\mathrm{Cl} = 3.0$$, what type of bond is present in $$\mathrm{HCl}$$?

Accepted Answer

Polar covalent

Question 9

Which of the following pairs of atoms would form the most polar covalent bond?

Accepted Answer

$$\mathrm{H}$$ and $$\mathrm{F}$$

Question 10

For the bond between $$\mathrm{N}$$ and $$\mathrm{H}$$, which atom is more negative and in which direction does the dipole point?

Accepted Answer

Nitrogen is more negative; dipole points toward nitrogen.

Question 11

Which of the following molecules is predicted to be linear according to VSEPR theory?

Accepted Answer

$$\mathrm{CO_2$}$$

Question 12

Which of the following best explains why $$\mathrm{H_2O} is a $$bent molecule rather than linear?

Accepted Answer

The two lone pairs on oxygen repel the bonding pairs, creating a bent shape.

Question 13

Which of the following is the correct Lewis structure for $$\mathrm{NH_3$}$$?

Accepted Answer

Nitrogen with three single bonds to hydrogen and one lone pair.

Question 14

A patient is given a medication containing $$\mathrm{Na_2SO_4}. $$Which ions are present in the solution after the compound dissolves in water?

Accepted Answer

$$\mathrm{Na^+}$$ and $$\mathrm{SO_4$^{2-}}$$

Question 15

Which of the following best describes the bond in $$\mathrm{NaCl}$$?

Accepted Answer

Ionic

Question 16

Which of the following molecules has a trigonal planar geometry according to VSEPR theory?

Accepted Answer

$$\mathrm{BF_3$}$$

Question 17

Which of the following statements about electronegativity is correct?

Accepted Answer

Electronegativity increases across a period and decreases down a group.

Question 18

Which of the following is the correct name for $$\mathrm{K_2SO_4}$$?

Accepted Answer

Potassium sulfate

Question 19

A molecule has the following Lewis structure: central atom with two single bonds and two lone pairs. What is the molecular geometry?

Accepted Answer

Bent

Question 20

Which of the following best explains why $$\mathrm{CO_2$} is a $$nonpolar molecule even though it contains polar bonds?

Accepted Answer

The molecule is linear, so the bond dipoles cancel each other out.

Exam 2 Study Guide: Ions, Compounds, Electronegativity, and Molecular Structure

Study Guide - Practice Questions