Atoms and Isotopes

Question 1

Name the three sub atomic particles

Answer 1

Protons, electrons and neutrons

Question 2

What is the mass of a proton?

Answer 2

1

Question 3

What is the mass of an electron?

Answer 3

Almost zero / very small

Question 4

What is the mass of a neutron?

Answer 4

1

Question 5

What is the mass number of an atom?

Answer 5

The total number of protons and neutrons in the atom

Question 6

What is the atomic number of an atom?

Answer 6

The number of protons (or electrons) in an atom

Question 7

What is the charge on a proton?

Answer 7

+1 / positive / +

Question 8

What is the charge on a neutron?

Answer 8

0 / zero / no charge

Question 9

What is the charge on an electron?

Answer 9

-1 / negative / -

Question 10

What is in the nucleus of an atom?

Answer 10

Protons and neutrons

Question 11

Where are the electrons found in an atom?

Answer 11

In the shells

Question 12

Sodium has a mass number of 23 and an atomic number of 11. How many protons, neutrons and electrons does it have?

Answer 12

11 protons
11 electrons
12 neutrons

Question 13

Carbon has an atomic number of 6. How many electrons does it have and how are they arranged?

Answer 13

6 electrons

2 in the first shell, 4 in the second shell (2.4)

Question 14

What name is given to atoms of the same element that have different numbers of neutrons?

Answer 14

Isotopes

Question 15

Why do the isotopes carbon-12 and carbon-14 have different mass numbers?

Answer 15

Carbon-12 has 6 neutrons and carbon-14 has 8 neutrons (they both have 6 protons and 6 electrons)

Question 16

Why does chlorine have a mass number that is not a whole number, 35.5?

Answer 16

The mass number is an average of the isotope mass numbers, taking into account their abundances (amounts).

Question 17

An atom with 3 protons has a mass number of 7. How many neutrons does it have?

Answer 17

4

Question 18

An atom has 7 protons, 7 neutrons and 7 electrons. How many of these sub-atomic particles are found in the nucleus?

Answer 18

14 (7 protons and 7 neutrons)

Question 19

An atom has 17 protons, 17 electron and 18 neutrons. In the isotope of this element, what will be different?

Answer 19

The number of neutrons

Question 20

A particle has 14 protons, 14 electrons and 15 neutrons. Is the particle an atom? Why?

Answer 20

Yes it is an atom.

It has the same number of positively charged protons and negatively charged electrons.

Question 21

An atom has 6 electrons. What is the symbol of this element?

Answer 21

C