Ch. 13 Nuclear Rxns

Question 1

How is the nucleus held together?

Answer 1

Nuclear binding energy

= energy holding neutrons and protons together

Question 2

Stability of nucleus is determined by

Answer 2

high stability = high nuclear binding energy

Question 3

What is mass defect?

Answer 3

the difference in mass between sum of protons and neutrons vs nucleus as a whole
(this is “m” in E = mc^2)

Question 4

What is greater in weight, sum of protons and neutrons or nucleus as a whole?

Answer 4

sum of protons and neutrons

because binding energy is converted to hold them together

Question 5

explain beta negative decay

Answer 5

neutron converted to proton and electron emitted

Question 6

explain beta positive decay

Answer 6

proton converted to neutron and positron emitted

Question 7

explain electron capture

Answer 7

positive nucleus captures an electron from innermost shell and combines it with proton to form a neutron
“+ve” + “-ve” => “0”

Question 8

Atomic number is equivalent to…

Answer 8

# protons
element identity