(English Medium) ICSE Class 9 - CISCE Question Bank Solutions for Chemistry

The atom of aluminium is represented by ²⁷Al₁₃. Write down the number of neutrons in the different orbits or shells in one atom of aluminium.

The atom of aluminium is represented by ²⁷Al₁₃. Write down the number of the arrangement of electrons in the different orbits or shells in one atom of aluminium.

What is meant by the term orbits

What are ‘energy levels’?

Explain the arrangement and distribution of electrons in the various shells with reference to an atom in general and to an atom of potassium ‘³⁹₁₉K’ with special reference to the 2n² rule.

Differentiate between the term Stable and unstable electronic configuration.

Differentiate between the term Duplet and octet rule.

The following element is given \[\ce{_3U}\]. State the electronic configuration and state whether it is a metal, non-metal, or inert gas.

The following element is given \[\ce{_6V}\]. State the electronic configuration and state whether it is a metal, non-metal, or inert gas.

The following element is given \[\ce{_9W}\]. State the electronic configuration and state whether it is a metal, non-metal, or inert gas.

The following element is given \[\ce{_14X}\]. State the electronic configuration and state whether it is a metal, non-metal, or inert gas.

The following element is given \[\ce{_18Y}\]. State the electronic configuration and state whether it is a metal, non-metal, or inert gas.

The following element is given \[\ce{_20Z}\]. State the electronic configuration and state whether it is a metal, non-metal, or inert gas.

Explain the octet rule for the formation of –

Sodium chloride from a sodium atom and a chlorine atom.

Explain the octet rule for the formation of –

Nitrogen molecule from two nitrogen atoms.

Select the correct answer from the answer in the bracket to complete the sentence.

The maximum number of electrons in M-shell is _______.

Give a reason for the following:

The shells surrounding the nucleus of an atom are also called ‘energy levels’.

Give a reason for the following:

Helium is chemical extremely unreactive.

Fill in the blank with the correct word from the options given below:

Relative molecular mass of an element/compound is the number of times one ________ of the substance is heavier than −1/12that the mass of an atom of carbon [C₁₂].

Calculate the relative molecular mass of ZnCO₃.