Q: What is the formula mass of $$\mathrm{CO_2$}$$? (Atomic masses: C = 12.0 u, O = 16.0 u)

$$12.0\ \mathrm{u} + 2 \times 16.0\ \mathrm{u} = 44.0\ \mathrm{u}$$

Question 1

Which statement best explains why the properties of table sugar (sucrose) are different from those of its constituent elements, carbon, hydrogen, and oxygen?

Accepted Answer

The atoms in sucrose are arranged in a fixed, definite proportion, resulting in new properties.

Question 2

According to the law of constant composition, which of the following statements is true for all samples of pure water?

Accepted Answer

All samples have a mass ratio of oxygen to hydrogen of $$\frac{16.0\ \mathrm{g}\ O}{2.0\ \mathrm{g}\ H} = 8.0$$

Question 3

Which of the following best distinguishes a compound from a mixture?

Accepted Answer

A compound has elements combined in fixed, definite proportions.

Question 4

What is the empirical formula for hydrogen peroxide, given its molecular formula is $$\mathrm{H}_2\mathrm{O}_2$$?

Accepted Answer

$$\mathrm{HO}$$

Question 5

Which of the following is a correct chemical formula for a compound containing magnesium and nitrate ions?

Accepted Answer

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

Question 6

How many oxygen atoms are present in one formula unit of $$\mathrm{Mg(NO_3$)_2}$$?

Accepted Answer

6

Question 7

Which of the following elements exists naturally as a diatomic molecule?

Accepted Answer

Chlorine ($$\mathrm{Cl}_2)$$

Question 8

Which of the following compounds is classified as an ionic compound?

Accepted Answer

$$\mathrm{NaCl}$$

Question 9

What is the correct name for the compound $$\mathrm{$$FeCl_3$$}$$?

Accepted Answer

iron(III) chloride

Question 10

Which of the following is the correct formula for aluminum oxide, given the charges $$\mathrm{Al}^{3+}$$ and $$\mathrm{O}^{2-}$$?

Accepted Answer

$$\mathrm{Al_2O_3}$$

Question 11

Which of the following is the correct name for $$\mathrm{$$KNO_3$$}$$?

Accepted Answer

potassium nitrate

Question 12

What is the correct name for $$\mathrm{N_2O_5}$$?

Accepted Answer

dinitrogen pentoxide

Question 13

Which of the following is the correct name for $$\mathrm{H_2SO_4} (aq$$)?

Accepted Answer

sulfuric acid

Question 14

A sample of ammonia ($$\mathrm{NH_3$}) is $$decomposed into 14.0 g of nitrogen and 3.0 g of hydrogen. What is the mass ratio of nitrogen to hydrogen in ammonia?

Accepted Answer

$$\frac{14.0\ \mathrm{g}\ N}{3.0\ \mathrm{g}\ H} = 4.7$$

Question 15

Which of the following is the correct formula for calcium phosphate, given the ions $$\mathrm{Ca}^{2+}$$ and $$\mathrm{PO_4$}^{3-}$$?

Accepted Answer

$$\mathrm{Ca_3$(PO_4$)_2}$$

Question 16

Which of the following is the correct name for $$\mathrm{$$HClO_2$$} (aq$$)?

Accepted Answer

chlorous acid

Question 17

What is the formula mass of $$\mathrm{CO_2$}$$? (Atomic masses: C = 12.0 u, O = 16.0 u)

Accepted Answer

$$12.0\ \mathrm{u} + 2 	imes 16.0\ \mathrm{u} = 44.0\ \mathrm{u}$$

Question 18

Which of the following is the correct name for $$\mathrm{Cu(NO_3$)_2}$$?

Accepted Answer

copper(II) nitrate

Question 19

Which of the following best describes the difference between a molecular and an ionic compound?

Accepted Answer

Molecular compounds are composed of two or more nonmetals, while ionic compounds are composed of metals and nonmetals.

Chapter 5: Molecules and Compounds – Structured Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards