Possible Atom Test Questions

Name_____________________________________Period____Date______________________ Chemistry - Possible Inside the Atom Test Questions

Multiple Choice

Identify the choice that best completes the statement or answers the question.




1. Atoms have no electric charge because they

a.	have an equal number of charged and noncharged particles.
b.	have neutrons in their nuclei.
c.	have an equal number of electrons and protons.
d.	have an equal number of neutrons and protons.

2. A subatomic particle that has a negative charge is called a(n)

a.	molecule.	c.	element.
b.	electron.	d.	compound.

3. Which of the following statements is not true?

a.	Protons have a positive charge.
b.	A nucleus has a positive charge.
c.	Neutrons have no charge.
d.	Neutrons have a negative charge.

4. What is an atom’s nucleus made of?

a.	protons and neutrons	c.	only neutrons
b.	only protons	d.	anodes

5. The charge of an atom is

a.	positive.	c.	negative.
b.	neutral.	d.	unbalanced.

6. An iron atom has an atomic mass of 56. Its atomic number is 26. How many neutrons does the iron atom have?

a.	30	c.	26
b.	56	d.	82

7. How much effect do high percent abundance isotopes have on the average atomic mass of an element?

a.	less than low percentage isotopes	c.	same as low percentage isotopes
b.	no effect on atomic mass	d.	more than low percentage isotopes

8. An element’s atomic number is equal to its number of

a.	protons.	c.	valence electrons
b.	neutrons.	d.	protons and neutrons.

9. Two different isotopes of an element have different

a.	numbers of neutrons.	c.	atomic numbers.
b.	numbers of protons.	d.	numbers of electrons.

10. What is the mass number of an element that has

19 protons, 19 electrons, and 20 neutrons?

a.	19	c.	39
b.	20	d.	58

11. Which statement about the atom’s nucleus is correct?

a.	The nucleus is made of protons and neutrons and has a negative charge.
b.	The nucleus is made of protons and neutrons and has a positive charge.
c.	The nucleus is made of electrons and has a positive charge.
d.	The nucleus is made of electrons and has a negative charge.

12. Oxygen’s atomic number is 8. This means that an oxygen atom has

a.	eight neutrons in its nucleus.
b.	a total of eight protons and neutrons.
c.	eight protons in its nucleus.
d.	a total of eight neutrons and electrons.

13. Which statement about an element’s average atomic mass is correct?

a.	It is determined by counting the number of isotopes in a sample of the element.
b.	It is equal to one-twelfth the mass of the most common isotope.
c.	It is a weighted average, so common isotopes have a greater effect than uncommon ones.
d.	It is based on an isotope’s charge, so negatively charged isotopes have a greater effect than positive ones.

14. An atom’s mass number equals the number of

a.	protons plus the number of electrons.
b.	protons plus the number of neutrons.
c.	protons.
d.	neutrons.

15. An allotrope of carbon that is hard and is often used in jewelry is ____.

a.	diamond	c.	quartz
b.	graphite	d.	silicon

16. A Ca²⁺ ion differs from a Ca⁰ atom in that the

Ca²⁺ ion has

a. more electrons c. fewer protons

b. more protons d. fewer electrons

17. How many electrons does an element have with a mass number of 36?

a. 36 c. 72

b. 18 d. unknown

18. The nucleus of an atom consists of 8 protons and

6 neutrons. The total number of electrons present

in a neutral atom of this element is

a. 6 c. 2

b. 8 d. 14
19. Atoms of ¹⁶O, ¹⁷O, and ¹⁸O have the same number of

a. protons, but a different number of electrons

b. electrons, but a different number of protons

c. protons, but a different number of neutrons

d. neutrons, but a different number of protons

20. All atoms of an element have the same

a. number of neutrons c. atomic number

b. atomic mass d. mass number
21. The atomic number is always equal to the total number of

a. neutrons in the nucleus

b. protons in the nucleus

c. neutrons plus protons in the atom

d. protons plus electrons in the atom
22. How many protons are in the nucleus of an atom of beryllium?

a. 2 c. 9

b. 4 d. 5
23. Which subatomic particle is negative?

a. proton c. electron

b. neutron d. nucleus

24. Which of the following particles has the least mass?

a. neutron c. electron

b. proton d. hydrogen nucleus

25. A sample of element X contains 90% X-35 atoms,

8.0% X-37 atoms, and 2.0% X-38 atoms. The

average atomic mass will be closest to which

value?

a. 35 c. 37

b. 36 d. 38

26. What is the total number of electrons in an Mg⁺² ion?

a. 10 c. 2

b. 24 d. 12

27. The atomic mass of an element is defined as the weighted average mass of that element’s

a. naturally occurring isotopes

b. least abundant isotope

c. radioactive isotopes

d. most abundant isotope

28. Compared to the entire atom, the nucleus of the atom is

a. smaller and contains most of the atom’s mass

b. smaller and contains little of the atom’s mass

c. larger and contains most of the atom’s mass

d. larger and contains little of the atom’s mass

29. What is the nuclear charge in an atom of boron?

a. +11 c. +5

b. +6 d. +12



30. Which symbols represent atoms that are isotopes?
a. C-14 and N-14  c. O-16 and O-18  b. I-131 and I-131 d. Rn-222 and Ra-222

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