Write the distribution of electrons in carbon and sodium atoms.

Important Questions on Test Paper 4

MEDIUM

9th CBSE

IMPORTANT

LIVING SCIENCE CHEMISTRY 9>Chapter 9 - Test Paper 4>Test Paper 4>Q 14

Isotopes find important applications in a variety of areas in the fields of medicine, agriculture, generation of cheaper electricity, industry, radiocarbon dating, etc.

a. Which isotope is used for detecting the thyroid disorder?
b. Which isotope is used to monitor the uptake of phosphorus by plants?
c. Which isotopes are used for the generation of cheaper electricity?
d. Which isotope is used to test the complete removal of phosphorus from steel in the manufacture of steel?
e. Which isotope is used for finding the age of a fossil?

MEDIUM

9th CBSE

IMPORTANT

LIVING SCIENCE CHEMISTRY 9>Chapter 9 - Test Paper 4>Test Paper 4>Q 15

Define valency by taking examples of silicon and oxygen.

MEDIUM

9th CBSE

IMPORTANT

LIVING SCIENCE CHEMISTRY 9>Chapter 9 - Test Paper 4>Test Paper 4>Q 17

Which separation techniques will you apply for the separation of the following mixtures?
a. Sodium chloride from its solution in water.
b. Ammonium chloride from a mixture containing sodium chloride and ammonium chloride.
c. Small pieces of metal from the engine oil of a car.
d. Benzene from a mixture of benzene and methylbenzene.
e. Different pigments from an extract of flower petals.

MEDIUM

9th CBSE

IMPORTANT

LIVING SCIENCE CHEMISTRY 9>Chapter 9 - Test Paper 4>Test Paper 4>Q 18

Calculate the mass of
a. 1 atom of nitrogen
b. 1 atom of silver
c. 1 molecule of benzene (C₆H₆).

MEDIUM

9th CBSE

IMPORTANT

LIVING SCIENCE CHEMISTRY 9>Chapter 9 - Test Paper 4>Test Paper 4>Q 19

How many molecules are present in
a.