1.2 The Nuclear Atom

Question 1

Subatomic particles

Answer 1

particles inside an atom (protons, neutrons, electrons)

Question 2

Mass of proton

Answer 2

1

Question 3

Mass of neutron

Answer 3

1

Question 4

Mass of electron

Answer 4

1/2000 (0)

Question 5

Charge of proton

Answer 5

+1

Question 6

Charge of neutron

Answer 6

0 (neutral)

Question 7

Charge of electron

Answer 7

-1

Question 8

Nucleus

Answer 8

very dense core of an atom consisting of protons and neutrons

Question 9

Nucleons

Answer 9

protons and neutrons

Question 10

What holds an atom together?

Answer 10

electrostatic attraction between protons and electrons

Question 11

A (subatomic particles)

Answer 11

mass number

Question 12

Z (subatomic particles)

Answer 12

atomic number

Question 13

Find neutrons (given A and Z)

Answer 13

A - Z

Question 14

Properties of a neutral atom

Answer 14

same number of electrons and protons

Question 15

Ion

Answer 15

atoms of the same element with a different number of electrons (lost/gained electrons)

Question 16

Isotope

Answer 16

atoms of the same element with a different number of neutrons

Question 17

Relative atomic mass formula

Answer 17

(mass1 * abundance1 + mass 2 * abundance2…) divided by 100

Question 18

Mass spectra

Answer 18

device used to record percentage abundance of isotopes

Question 19

Oxide ion (in the form A, Z, X, i+-)

Answer 19

16, 8, O, 2-

Question 20

Why isn’t the relative atomic mass always a whole number in the periodic table?

Answer 20

it measures the average mass of it’s isotopes which might not necessarily be an integer

Question 21

Natural abundance

Answer 21

relative percentage of an isotope compared to all other isotopes of that element on earth

Question 22

Natural abundance of Cl-35 and Cl-37 (Ar = 35.5)

Answer 22

Cl-35: 75%; Cl-37: 25%

Question 23

Why do isotopes share chemical properties?

Answer 23

change in the number of neutrons does not affect electron arrangement which determines chemical properties

Question 24

Two main isotopes of U

Answer 24

U-235 & U-238

Question 25

Why is one isotope of U preferred in nuclear reactors?

Answer 25

U-235 is preferred due to better fission capabilities of their lighter mass

Question 26

Main mass of an atom is contained in?

Answer 26

the nucleus