Question 1

Which of the following statements best explains why the properties of table sugar (sucrose, $$\mathrm{C$$_{12}$$H_{22}O$$_{11}}$) are different from those of its component elements?

Accepted Answer

When elements combine to form a compound, they do so in fixed ratios and the resulting compound has unique properties distinct from its elements.

Question 2

According to the Law of Constant Composition, which of the following is true for any pure sample of water?

Accepted Answer

The mass ratio of oxygen to hydrogen is always $$8.0:1.$$

Question 3

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

Accepted Answer

A compound has a fixed, definite proportion of elements, while a mixture has variable proportions.

Question 4

If you change the subscript in the chemical formula $$\mathrm{CO} to$$ $$\mathrm{CO_2$}$$, what is the result?

Accepted Answer

You have created a completely different compound with different properties.

Question 5

Which of the following is the correct empirical formula for hydrogen peroxide, given its molecular formula is $$\mathrm{H_2O_2}$$?

Accepted Answer

$$\mathrm{HO}$$

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 substances is classified as a molecular element?

Accepted Answer

Chlorine gas ($$\mathrm{Cl_2$})$$

Question 8

Which of the following is the correct chemical formula for the ionic compound formed between magnesium and chlorine?

Accepted Answer

$$\mathrm{$$MgCl_2$$}$$

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 name for $$\mathrm{$$KNO_3$$}$$?

Accepted Answer

Potassium nitrate

Question 11

What is the correct formula for ammonium sulfate?

Accepted Answer

$$\mathrm{(NH_4$)_2SO_4}$$

Question 12

Which of the following 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 and found to contain 14.0 g of nitrogen and 3.0 g of hydrogen. What is the mass ratio of nitrogen to hydrogen in ammonia?

Accepted Answer

$$4.7:1$$

Question 15

Which of the following best describes the basic unit of an ionic compound?

Accepted Answer

A formula unit composed of cations and anions in a 3D array

Question 16

Which of the following is the correct name for $$\mathrm{$$HNO_2$$} (aq$$)?

Accepted Answer

Nitrous acid

Question 17

Which of the following is the correct formula for calcium phosphate?

Accepted Answer

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

Question 18

Which of the following is a correct statement about naming binary molecular compounds?

Accepted Answer

The more metal-like element is named first, and prefixes indicate the number of each atom.

Question 19

Which of the following is the correct name for $$\mathrm{NaClO}$$, the active ingredient in household bleach?

Accepted Answer

Sodium hypochlorite

Question 20

A compound contains 2 atoms of aluminum and 3 groups of sulfate ($$\mathrm{SO_4$^{2-}}). $$What is its correct chemical formula?

Accepted Answer

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

Chapter 5: Molecules and Compounds – Study Notes for Introductory Chemistry

Guida di studio - Domande di pratica

Study guide - Flashcard