Question 1

Which of the following is NOT a SI unit for measurements in chemistry?

Accepted Answer

Liter

Question 2

A family-size chocolate bar is 15 cm long. If you measure it as 15.00 cm, which of the following best describes this measurement?

Accepted Answer

It is a measured number with three significant figures.

Question 3

Express the number 0.000045 in scientific notation.

Accepted Answer

$4.5 	imes 10^{-5}$

Question 4

Which of the following is an example of an exact number?

Accepted Answer

There are 12 eggs in a dozen.

Question 5

A student dissolves 8.456 g of sugar in water. How many significant figures are in this measurement?

Accepted Answer

4

Question 6

A medication label states: 'Take 0.75 mg per tablet.' If a patient needs 60 mg, how many tablets should they take?

Accepted Answer

80 tablets

Question 7

Which of the following is a heterogeneous mixture?

Accepted Answer

Blood

Question 8

A car travels 30 miles in 0.5 hours. What is its average speed in miles per hour?

Accepted Answer

$60\ 	ext{mi/hr}$

Question 9

Which of the following elements is a noble gas?

Accepted Answer

Ne

Question 10

What is the atomic number of sodium (Na)?

Accepted Answer

11

Question 11

How many protons, neutrons, and electrons are in an atom of $^{23}_{11}	ext{Na}$?

Accepted Answer

11 protons, 12 neutrons, 11 electrons

Question 12

Which of the following statements about isotopes is TRUE?

Accepted Answer

Isotopes have the same number of protons but different numbers of neutrons.

Question 13

Which element has the greatest positive charge on its nucleus among Na, F, and Cl?

Accepted Answer

Cl

Question 14

How many electrons can occupy the 2p orbital of silicon?

Accepted Answer

6

Question 15

Which of the following is a chemical property?

Accepted Answer

Reactivity with oxygen

Question 16

Which of the following is a pure substance?

Accepted Answer

Copper

Question 17

If a sodium atom has a mass number of 24, how many neutrons does it have?

Accepted Answer

13

Question 18

Which of the following is the correct electron configuration for sodium (Na)?

Accepted Answer

$1s^2\ 2s^2\ 2p^6\ 3s^1$

Question 19

Which of the following elements is in Group 1A of the periodic table?

Accepted Answer

Li

Question 20

Which statement about the 3s, 3p, and 3d orbitals is correct?

Accepted Answer

They have the same energy level but different shapes.

CHEM 151: Review Exam I Study Guide – Fundamental Concepts in GOB Chemistry

Study Guide - Practice Questions