Question 1

Which of the following statements best describes a compound?

Accepted Answer

A substance in which two or more different elements are chemically bonded together.

Question 2

Which of the following is an example of a diatomic element?

Accepted Answer

Oxygen gas, $$O_2$$

Question 3

Which property is NOT characteristic of metals?

Accepted Answer

They are poor conductors of electricity.

Question 4

Which of the following elements is a metalloid?

Accepted Answer

Silicon, $$Si$$

Question 5

Which group of the periodic table contains the noble gases?

Accepted Answer

Group 8A

Question 6

Which of the following is a property of nonmetals?

Accepted Answer

They are often gases or brittle solids at room temperature.

Question 7

Which element is most abundant in the universe?

Accepted Answer

Hydrogen

Question 8

Which of the following best explains why metalloids are used in the electronics industry?

Accepted Answer

They are semiconductors whose conductivity can be controlled by doping.

Question 9

Which of the following elements is a liquid nonmetal at room temperature?

Accepted Answer

Bromine, $$Br_2$$

Question 10

Which of the following is a correct statement about allotropes?

Accepted Answer

Allotropes are different structural forms of the same element.

Question 11

Which of the following elements is a main group metal?

Accepted Answer

Sodium, $$Na$$

Question 12

Which of the following best describes the difference between a period and a group on the periodic table?

Accepted Answer

A period is a horizontal row; a group is a vertical column.

Question 13

Which of the following elements is a transition metal?

Accepted Answer

Copper, $$Cu$$

Question 14

Which of the following is a real-life application of the reactivity of alkali metals?

Accepted Answer

Sodium is stored under oil to prevent reaction with water.

Question 15

Which of the following best explains why noble gases are unreactive?

Accepted Answer

They have a full valence shell of electrons.

Question 16

Which of the following is a correct chemical equation for the reaction of sodium with chlorine gas?

Accepted Answer

$$2Na(s) + Cl_2$(g) \rightarrow 2NaCl(s)$$

Question 17

Which of the following elements is most likely to be found as a molecule in nature?

Accepted Answer

Nitrogen, $$N_2$$

Question 18

Which of the following statements about hydrogen is correct?

Accepted Answer

Hydrogen is the most abundant element in the universe.

Question 19

Which of the following is a correct statement about the physical state of elements at room temperature?

Accepted Answer

Most nonmetals are gases or brittle solids at room temperature.

Question 20

Which of the following best describes the role of stratospheric ozone?

Accepted Answer

It protects the Earth from ultraviolet (UV) radiation.

Elements, Compounds, and the Periodic Table: Structure and Classification

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