$$^{14}_{7}\mathrm{N}$$ \, \text{and} \, ^{18}_{7}\mathrm{N}$

Question 1

Which of the following statements best describes an atom?

Accepted Answer

An atom is the smallest particle of an element that retains the chemical properties of that element.

Question 2

Which subatomic particle has the smallest mass?

Accepted Answer

Electron

Question 3

Given the element symbol $$^{23}_{11}\mathrm{Na}$$, how many protons, neutrons, and electrons are present in a neutral atom?

Accepted Answer

11 protons, 12 neutrons, 11 electrons

Question 4

What is the mass number ($$A) of an $$atom with 26 protons and 29 neutrons?

Accepted Answer

$$A = 55$$

Question 5

A zinc atom has a mass number of 65 and an atomic number of 30. How many neutrons does it have?

Accepted Answer

35 neutrons

Question 6

Which of the following is an isotope of $$^{238}_{92}\mathrm{U}$$?

Accepted Answer

$$^{239}_{92}\mathrm{U}$$

Question 7

Which two notations represent isotopes of the same element?

Accepted Answer

$$^{14}_{7}\mathrm{N}$$ \, 	ext{and} \, ^{18}_{7}\mathrm{N}$

Question 8

Which group on the periodic table contains the least reactive elements?

Accepted Answer

Group 8A (Noble gases)

Question 9

What is the atomic number ($$Z) of an $$element with 79 protons?

Accepted Answer

$$Z = 79$$

Question 10

Which of the following best explains why isotopes of the same element have identical chemical properties?

Accepted Answer

They have the same number of protons and electrons.

Question 11

A patient undergoes a Tc-99 scan to trace blood flow in the heart. What property of Tc-99 makes it useful for this purpose?

Accepted Answer

It is a radioactive isotope that emits detectable energy.

Question 12

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

Accepted Answer

Potassium (K)

Question 13

If an atom has 15 protons, 16 neutrons, and 15 electrons, what is its mass number?

Accepted Answer

$$A = 31$$

Question 14

Which of the following statements about the periodic law is correct?

Accepted Answer

The physical and chemical properties of elements are periodic functions of their atomic numbers.

Question 15

Which of the following is the correct symbolic representation for an atom with 17 protons and 18 neutrons?

Accepted Answer

$$^{35}_{17}\mathrm{Cl}$$

Question 16

Which of the following elements is a halogen?

Accepted Answer

Chlorine (Cl)

Question 17

How many electrons are present in a neutral atom of gold ($$^{197}_{79}\mathrm{Au}$$)?

Accepted Answer

79 electrons

Question 18

Which of the following best describes the location of electrons in an atom?

Accepted Answer

Electrons are located outside the nucleus, moving rapidly in a large volume of space.

Question 19

Which of the following elements is in Group 2A (alkaline earth metals)?

Accepted Answer

Magnesium (Mg)

Question 20

A neutral atom of boron is represented as $$^{11}_{5}\mathrm{B}. $$How many neutrons does it have?

Accepted Answer

6 neutrons

Atoms and Elements: Structure, Properties, and the Periodic Table

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