Question 1

Which of the following best describes a mixture?

Accepted Answer

A combination of two or more substances that retain their individual properties and can be separated by physical means.

Question 2

Which region of the periodic table contains the noble gases?

Accepted Answer

Group 18 (far right column)

Question 3

Express the number 0.0004560 in scientific notation with the correct number of significant figures.

Accepted Answer

$$4.560 	imes 10$$^{-4}$$

Question 4

How many significant figures are in the measurement 0.02030 g?

Accepted Answer

4

Question 5

A patient receives a medication dose of 0.250 g. Convert this mass to milligrams (mg).

Accepted Answer

$$250 mg$$

Question 6

Which of the following correctly converts 37.0 $$^\circC to $$Kelvin?

Accepted Answer

$$37.0 + 273.15 = 310.15 K$$

Question 7

Which statement about subatomic particles is correct?

Accepted Answer

Electrons are found outside the nucleus and have a negative charge.

Question 8

An atom of $$^{35}_{17}\mathrm{Cl}$$ has how many neutrons?

Accepted Answer

18

Question 9

Which of the following is the correct representation for an isotope of carbon with 7 neutrons?

Accepted Answer

$$^{13}_{6}\mathrm{C}$$

Question 10

How many valence electrons does a phosphorus atom have?

Accepted Answer

5

Question 11

Which of the following is a correct Lewis dot symbol for magnesium (Mg)?

Accepted Answer

$$\cdot \mathrm{Mg} \cdot$$

Question 12

Which of the following is the correct name for the compound $$\mathrm{N}_2\mathrm{O}_5$$?

Accepted Answer

Dinitrogen pentoxide

Question 13

Which of the following best defines a covalent bond?

Accepted Answer

A bond formed by the sharing of electron pairs between atoms.

Question 14

A sample of water is measured as 25.0 mL. What is this volume in liters (L)?

Accepted Answer

$$0.0250 L$$

Question 15

A thermometer reads 98.6 $$^\circF. $$What is this temperature in Celsius?

Accepted Answer

$$37.0^\circC$$

Question 16

Which of the following is a correct binary covalent compound formula for 'carbon tetrachloride'?

Accepted Answer

$$\mathrm{CCl}_4$$

Question 17

A student needs to prepare 0.500 L of a solution. How many milliliters (mL) is this?

Accepted Answer

$$500 mL$$

Question 18

Which of the following statements about isotopes is correct?

Accepted Answer

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

Question 19

Which of the following is the correct number of protons, neutrons, and electrons in $$^{23}_{11}\mathrm{Na}$$?

Accepted Answer

11 protons, 12 neutrons, 11 electrons

Question 20

Which of the following best describes the process for drawing a Lewis structure for $$\mathrm{CO}_2$$?

Accepted Answer

Count total valence electrons, connect atoms with single bonds, complete octets, and use double bonds if needed to satisfy the octet rule.

Study Guide: Matter, Measurement, Atoms, and Covalent Bonding

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