$$19$$\text{ protons},\ 20$$\text{ neutrons},\ 18$$\text{ electrons}

Question 1

Which of the following best describes a metalloid based on its physical and chemical properties?

Accepted Answer

A brittle solid that conducts electricity moderately well and can be shiny or dull.

Question 2

Which group on the periodic table contains the halogens?

Accepted Answer

7A

Question 3

According to the octet rule, how do elements on the left side of the periodic table typically achieve a stable electron configuration?

Accepted Answer

By losing electrons to reach the previous noble gas configuration.

Question 4

Which of the following elements will form an ion with a charge of $$+3$$?

Accepted Answer

Al

Question 5

How many electrons are present in a $$\mathrm{P$$^{3-}$$}$$ ion?

Accepted Answer

$$18$$

Question 6

A potassium ion ($$\mathrm{K^+}) $$has how many protons, neutrons, and electrons? (Potassium atomic number = 19, mass number = 39)

Accepted Answer

$$19$$	ext{ protons},\ 20$$	ext{ neutrons},\ 18$$	ext{ electrons}

Question 7

Which of the following ions is isoelectronic with neon ($$\mathrm{Ne}$$)?

Accepted Answer

$$\mathrm{Na^+}$$

Question 8

Which of the following statements about transition metals is correct?

Accepted Answer

Transition metals can form ions with different positive charges.

Question 9

Which of the following atoms will form an ion with a charge of $$-1$$?

Accepted Answer

I

Question 10

How many electrons are present in an $$\mathrm{O$$^{2-}$$}$$ ion?

Accepted Answer

$$10$$

Question 11

Which of the following best explains why sodium ($$\mathrm{Na}) $$forms a $$+1$$ ion?

Accepted Answer

It loses one electron to achieve the configuration of neon.

Question 12

A sample contains $$\mathrm{Mg$$^{2+}$$}$$ ions. How many electrons does each ion have? (Atomic number of Mg = 12)

Accepted Answer

$$10$$

Question 13

Which of the following is a property of nonmetals?

Accepted Answer

Powdery solids or gases

Question 14

Which of the following ions has the same number of electrons as a neutral sulfur atom?

Accepted Answer

$$\mathrm{Ca$$^{2+}$$}$$

Question 15

Which of the following elements is most likely to form a cation?

Accepted Answer

Sodium

Question 16

What is the charge on the ion formed by magnesium?

Accepted Answer

$$+2$$

Question 17

Which of the following ions is formed when an atom gains two electrons?

Accepted Answer

$$\mathrm{O$$^{2-}$$}$$

Question 18

A brittle solid that is a moderate conductor of electricity and is used in computer chips is most likely a:

Accepted Answer

Metalloid

Question 19

Which of the following ions has 18 electrons?

Accepted Answer

$$\mathrm{K^+}$$

Question 20

Which of the following best describes the trend for the formation of anions among nonmetals?

Accepted Answer

Nonmetals tend to gain electrons to achieve the configuration of the nearest noble gas.

Atoms, Elements, and Ion Formation: Properties and Classification

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