Question 1

A sample is analyzed using Photoelectron Spectroscopy (PES), and the spectrum shows three distinct peaks with relative intensities of 2:2:6. Which element is most likely present in the sample?

Accepted Answer

Carbon ($\mathrm{C}$)

Question 2

A compound contains 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. What is the empirical formula of the compound?

Accepted Answer

$\mathrm{CH}_2\mathrm{O}$

Question 3

Which of the following compounds is most likely to contain an ionic bond?

Accepted Answer

$\mathrm{NaCl}$

Question 4

What is the correct name for the compound $\mathrm{FeCl}_3$?

Accepted Answer

Iron(III) chloride

Question 5

Which formula is correct for dinitrogen pentoxide?

Accepted Answer

$\mathrm{N}_2\mathrm{O}_5$

Question 6

A sample of a compound is combusted and produces 4.40 g of $\mathrm{CO}_2$ and 1.80 g of $\mathrm{H}_2\mathrm{O}$. What is the empirical formula of the compound?

Accepted Answer

$\mathrm{CH}_2\mathrm{O}$

Question 7

Which of the following reactions is a redox reaction?

Accepted Answer

$\mathrm{2H}_2 + \mathrm{O}_2 \rightarrow \mathrm{2H}_2\mathrm{O}$

Question 8

Balance the following chemical equation: $\mathrm{C}_3\mathrm{H}_8 + \mathrm{O}_2 \rightarrow \mathrm{CO}_2 + \mathrm{H}_2\mathrm{O}$

Accepted Answer

$\mathrm{C}_3\mathrm{H}_8 + 5\mathrm{O}_2 \rightarrow 3\mathrm{CO}_2 + 4\mathrm{H}_2\mathrm{O}$

Question 9

Which of the following is a double replacement reaction?

Accepted Answer

$\mathrm{Na}_2\mathrm{SO}_4 + \mathrm{BaCl}_2 \rightarrow \mathrm{BaSO}_4 + 2\mathrm{NaCl}$

Question 10

A compound is found to have a molar mass of 180 g/mol and an empirical formula of $\mathrm{CH}_2\mathrm{O}$. What is its molecular formula?

Accepted Answer

$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6$

Question 11

Which of the following best describes the Law of Definite Proportions?

Accepted Answer

A chemical compound always contains exactly the same proportion of elements by mass.

Question 12

What is the oxidation number of sulfur in $\mathrm{H}_2\mathrm{SO}_4$?

Accepted Answer

+6

Question 13

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

Accepted Answer

$\mathrm{Al}_2\mathrm{(SO}_4)_3$

Question 14

Which of the following is a synthesis reaction?

Accepted Answer

$\mathrm{2H}_2 + \mathrm{O}_2 \rightarrow \mathrm{2H}_2\mathrm{O}$

Question 15

Which of the following compounds is named correctly according to the prefix system for covalent compounds?

Accepted Answer

Carbon monoxide ($\mathrm{CO}$)

Question 16

A student mixes solutions of lead(II) nitrate and potassium iodide. A yellow precipitate forms. What type of reaction has occurred?

Accepted Answer

Double replacement

Question 17

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

Accepted Answer

$\mathrm{Ca}_3\mathrm{(PO}_4)_2$

Question 18

Which of the following is a combustion reaction?

Accepted Answer

$\mathrm{C}_2\mathrm{H}_4 + 3\mathrm{O}_2 \rightarrow 2\mathrm{CO}_2 + 2\mathrm{H}_2\mathrm{O}$

Question 19

A compound is found to be 27.3% carbon, 72.7% oxygen by mass. What is the empirical formula?

Accepted Answer

$\mathrm{CO}_2$

AP Chemistry Chapter 3: Atomic Structure, Bonding, and Chemical Reactions

Study Guide - Practice Questions

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