ICSE ICSE Class 8 - CISCE Question Bank Solutions

 Tick the most appropriate answer.

How many times is a proton heavier than an electron?

1. 1500
2. 1800
3. 1840
4. none of these

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β-particles are actually a stream of

1. protons
2. electrons
3. neutrons
4. none of these

TRUE \ FALSE

Electrons are present in the nucleus.

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What is an atom?

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Describe a discharge tube.

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What do you mean by electron transition?

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Name the isotopes of hydrogen.

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What is the charge on a neutron ?

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What is the number of neutrons present in a potassium atom ?

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Name the three subatomic particles. How are they different from each other ?

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What is the maximum number of electrons that L shell can accommodate ? Give reasons for your answer.

Draw the electronic configuration of the following elements clearly stating the number of neutrons and protons in their nucleus.
a. Beryllium b. Silicon
c. Chlorine d. Aluminium
e. Nitrogen

ANSWER IN DETAIL

Write a note on valence shell.

Indicate which of the following statement is true and which is false: 

The reaction between hydrogen and nitrogen to form ammonia is reversible.

Give reasons for the following:

 Hydrogen can be used as a fuel.

Classify the following changes as physical or chemical:- melting of a solid (wax)

Classify the following changes as physical or chemical:- photosynthesis in plants

Classify the following changes as physical or chemical:-boiling

Write two physical properties of hydrogen.

What is hydrogenation?