Question 1

Which statement best describes the law of constant composition as it applies to water?

Accepted Answer

All samples of pure water contain hydrogen and oxygen in a fixed mass ratio.

Question 2

A student decomposes 36.0 grams of water and obtains 32.0 grams of oxygen. According to the law of constant composition, how many grams of hydrogen should be produced?

Accepted Answer

$4.0$ grams

Question 3

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

Accepted Answer

A compound contains elements in fixed, definite proportions.

Question 4

What is the empirical formula for glucose, $C_6H_{12}O_6$?

Accepted Answer

$CH_2O$

Question 5

Which of the following is a molecular compound?

Accepted Answer

CO$_2$

Question 6

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

Accepted Answer

6

Question 7

Which of the following formulas represents an ionic compound?

Accepted Answer

KNO$_3$

Question 8

What is the correct name for $FeCl_2$?

Accepted Answer

Iron(II) chloride

Question 9

Which of the following is the correct formula for aluminum oxide?

Accepted Answer

$Al_2O_3$

Question 10

A compound contains 14.0 g of nitrogen and 3.0 g of hydrogen. What is the mass ratio of nitrogen to hydrogen in this compound?

Accepted Answer

$4.67:1$

Question 11

Which of the following is the correct name for $Na_2SO_4$?

Accepted Answer

Sodium sulfate

Question 12

What is the formula mass of $MgCl_2$? (Atomic masses: Mg = 24.3, Cl = 35.5)

Accepted Answer

$95.3$

Question 13

Which of the following is a binary acid?

Accepted Answer

HCl(aq)

Question 14

What is the correct name for $H_2SO_3$(aq)?

Accepted Answer

Sulfurous acid

Question 15

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

Accepted Answer

Oxygen

Question 16

What is the correct formula for calcium nitrate?

Accepted Answer

$Ca(NO_3)_2$

Question 17

Which of the following is the correct name for $N_2O_5$?

Accepted Answer

Dinitrogen pentoxide

Question 18

Which of the following compounds contains a polyatomic ion?

Accepted Answer

NaNO$_3$

Question 19

What is the correct name for $KClO_4$?

Accepted Answer

Potassium perchlorate

Question 20

Which of the following best explains why the properties of sodium chloride differ from those of sodium and chlorine?

Accepted Answer

Sodium chloride is a compound with a fixed ratio of sodium to chlorine, resulting in new properties.

Chapter 5: Molecules and Compounds – Structured Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards