Nuclear and Particle

Question 1

Unified atomic mass unit

Answer 1

1/12th of the mass of a carbon 12 atom. 1amu = 1.661 *10^-27kg

Question 2

Proton number Z

Answer 2

the number of protons inside a nucleus of a particular atom. Z

Question 3

Nucleons number A

Answer 3

The number of nucleons (protons and neutrons) inside the nucleus of a particular atom

Question 4

Isotopes

Answer 4

Atoms of the same element which contain the same number of protons but varying numbers of neutrons.

Question 5

Alpha particle scattering conclusions

Answer 5

• vast majority of mass is centred in the nucleus
• the nucleus has positive charge
• nucleus diameter is considerably smaller than the diameter of the atom

Question 6

The strong nuclear force

Answer 6

Acts between nucleons and holds the nucleus together against the electrostatic repulsion of the protons

Question 7

Fundamental particles

Answer 7

Particles that cannot be broken down further

Question 8

Hadrons

Answer 8

Whole number of charge due to quark charge. Examples are neutrons and protons

Question 9

Leptons

Answer 9

Fundamental particles. Examples are electrons and neutrinos

Question 10

A neutrino

Answer 10

A fundamental particle with almost no mass and no charge. Antiparticle = antineutron

Question 11

Quarks

Answer 11

Components of hadrons, have a fractional electronic charge

Question 12

The weak nuclear force

Answer 12

Felt by both quarks and leptons. Changed quarks from one type to another

Question 13

Radioactive decay

Answer 13

Is the spontaneous and random decay of an unstable nucleus

Question 14

Beta minus decay

Answer 14

Gives off an electron and a antineutrino

Question 15

Beta plus decay

Answer 15

Gives off a positron and a neutrino

Question 16

Alpha decay

Answer 16

Gives off an alpha particle and a gamma ray

Question 17

Activity

Answer 17

The number of decays per unit time. Measured in becquerels

Question 18

The decay constant λ

Answer 18

The probability that an individual nucleus will decay per unit time

Question 19

Carbon decay

Answer 19

A technique used to determine the age of organic matter from the relative proportions of the carbon-12 and carbon-14 isotopes it contains using the half life of carbon-14

Question 20

Annihilation

Answer 20

The process in which a particle and its antiparticle interact and their combined mass is converted to energy using E = mc^2

Question 21

Binding energy

Answer 21

The minimum energy required to separate the nucleus