Discovery of neutron and its properties

Question 5.4: State Chadwick experiment for discovery of neutron. Also write down any four properties of neutron.

Answer: In 1932, Chadwick discovered neutrons based on upon his studies on artificial radioactivity. He bombarded the beryllium (Be) target with a stream of a α-particles obtained from polonium source as shown in fig. He noticed that some penetrating radiations were produced. These radiations were called neutrons because the charged detector showed them to be neutral. The nuclear reaction is as follows. Properties of neutron.

1. neutrons cannot ionize gases.

2. Neutrons are highly penetrating particles.

3. They can expel high speed protons from paraffin, water, paper and cellulose.

4 they are used as projectile in nuclear reactions.

Slow neutrons are usually more effective than slow neutron for nuclear fission reaction.

Figure: Discovery of neutron

Question 5.5: Compare the properties of electron, proton and neutron.

Answer: Properties of electron, proton and neutron

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