basic science

Question 1

Atomic Structure

Answer 1

Max no of electrons in shell (n) =2n2

Question 2

Isotopes

Answer 2

nuclides same Z different N

Question 3

isotones

Answer 3

nuclides same N different N

Question 4

Isobars

Answer 4

nuclides same A

Question 5

BINDING ENERGY

Answer 5

The amount of energy needed to eject an electron from its shell.
The nearer to the nucleus the greater the binding energy
K shell electrons have a greater binding energy than M shell electrons.

Question 6

Ionisation

Answer 6

An orbital electron is given enough energy to be ejected from the atom.
It leaves a vacancy which is filled from the next shell out.
This gives rise to characteristic radiation.

Question 7

EXCITATION

Answer 7

When an orbital electron is given enough energy to be ejected from its shell but not enough to leave the atom.
It moves up to a outer orbit then drops back.
Gives the extra energy as characteristic radiation.

Question 8

Nuclear Stability

Answer 8

There is an electrostatic Repulsive force between protons in the nucleus.
There is a weaker nuclear Attractive force between all nucleons
As the nucleus gets bigger you need more and more neutrons to stop the nucleus from flying apart.

Question 9

The Cyclotron

Answer 9

Uses an oscillating magnetic field to accelerate positively charged particles
These particles are fired at a target material.
They are forced into the nucleus increasing the number of protons

Question 10

Radioactive (physical) Half Life

Answer 10

THE TIME TAKEN FOR THE ACTIVITY OF A RADIOACTIVE ELEMENT TO FALL TO ONE HALF ITS ORIGINAL VALUE DUE TO THE PROCESS OF RADIOACTIVE DECAY.

Question 11

Bremsstrahlung

Answer 11

Electron is slowed down by the electric field around the nucleus
Energy is transformed into X-rays
Continuous spectrum
Dependent on Z of material
Radiation protection - use light materials e.g. plastic