Question 1

Which of the following best describes the Octet Rule for main group elements?

Accepted Answer

Atoms tend to gain, lose, or share electrons to achieve a total of eight electrons in their outermost shell.

Question 2

What is the electron configuration for the Mg$$^{2+}$$ ion?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^6$$

Question 3

How many electrons does magnesium (Mg) lose to form a Mg$$^{2+}$$ ion?

Accepted Answer

2

Question 4

Which of the following ions has the same electron configuration as neon (Ne)?

Accepted Answer

Na$$^+$$

Question 5

What is the condensed electron configuration for the Na$$^+$$ ion?

Accepted Answer

$$[He]2s^2$ 2p^6$

Question 6

When a non-metal forms an anion, what happens to its electron configuration?

Accepted Answer

Electrons are added to the orbitals with available space.

Question 7

Which of the following is the correct electron configuration for the N$$^{3-}$$ ion?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^6$$

Question 8

A Cl$$^-$$ ion has the same electron configuration as which noble gas?

Accepted Answer

Argon (Ar)

Question 9

Which of the following best explains why metals tend to lose electrons?

Accepted Answer

To achieve the electron configuration of the nearest noble gas.

Question 10

What is the electron configuration for the O$$^{2-}$$ ion?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^6$$

Question 11

Which step is necessary when writing the electron configuration for a cation?

Accepted Answer

Remove electrons from the highest numbered shell.

Question 12

Which of the following ions is isoelectronic with Mg$$^{2+}$$?

Accepted Answer

O$$^{2-}$$

Question 13

If a sodium atom loses one electron, what is the resulting charge and electron configuration?

Accepted Answer

Charge: +1, Electron configuration: $$1s^2$$ $$2s^2$$ $$2p^6$$

Question 14

Which of the following statements about electron configurations is correct?

Accepted Answer

Anions have more electrons than their neutral atoms.

Question 15

What is the condensed electron configuration for the Cl$$^-$$ ion?

Accepted Answer

$$[Ne]3s^2$ 3p^6$

Question 16

Which of the following ions would you expect to be most stable based on the octet rule?

Accepted Answer

O$$^{2-}$$

Question 17

A student claims that the electron configuration for N$$^{3-} is$$ $$1s^2$$ $$2s^2$$ $$2p^3. Is $$this correct? Why or why not?

Accepted Answer

No, because N$$^{3-}$$ has gained three electrons, making its configuration $$1s^2$$ $$2s^2$$ $$2p^6.$$

Question 18

Which of the following ions does NOT have a noble gas electron configuration?

Accepted Answer

Mg$$^+$$

Question 19

What is the main reason non-metals tend to gain electrons?

Accepted Answer

To achieve a stable octet in their outermost shell.

Question 20

Which of the following is the correct step when writing the electron configuration for an anion?

Accepted Answer

Add electrons to the orbitals that can accommodate more electrons.

Ions, the Octet Rule, and Electron Configurations

Study Guide - Practice Questions