Radioactivity

Page 1

ALPHA PARTICLES

very ionising; will cause the atoms to become ions by making them lose electrons. dangerous to the human body.

can be deflected using a small angle to the NEGATIVE side of a field.

poorly penetrating: can be stopped by paper.

used in smoke alarms

travels a few cms

BETA PARTICLES.

fairly ionising

can be deflected with a small angle to the POSITIVE side of a field

fairly penetrating; will be stopped by a few centimetres of aluminium.

used in thickness monitoring

travels approx. half a meter

GAMMA PARTICLES

weakly ionising

cannot be deflected

very penetrating; stopped by lead/concrete.

used in medical tracers.

travels lots of m.

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Alpha Decay

When an atom undergoes alpha decay it loses 2 protons and 2 neutrons.

4 is subtracted from the atomic mass and 2 is subtracted from the atomic number.

This gives you the new atomic mass for new particles

Beta Decay

When anatom undergoes beta decay is lo

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DETECTION OF RADIATION

Particles can be detected by photographic film.