English Medium कक्षा ९ - CBSE Question Bank Solutions

Find the ratio by mass of the combining elements in the following compounds. (You may use Appendix-III)

C₂H₅OH

Find the ratio by mass of the combining elements in the following compounds. (You may use Appendix-III)

NH₃

Find the ratio by mass of the combining elements in the following compounds. (You may use Appendix-III)

Ca(OH)₂

Formula of sodium carbonate is ———— and that of ammonium sulphate is ————.

Which of the following are true for an element?

1. Atomic number = number of protons + number of electrons
2. Mass number = number of protons + number of neutrons
3. Atomic mass = number of protons = number of neutrons
4. Atomic number = number of protons = number of electrons

The ratio of the radii of hydrogen atom and its nucleus is ~ 10⁵. Assuming the atom and the nucleus to be spherical,

1. what will be the ratio of their sizes?
2. If atom is represented by planet earth ‘Re ’ = 6.4 ×106 m, estimate the size of the nucleus.

Show diagrammatically the electron distributions in a sodium atom and a sodium ion and also give their atomic number.

Which cell organelle plays a crucial role in detoxifying many poisons and drugs in a cell?

The cell organelle involved in forming complex sugars from simple sugars are

Silver nitrate solution is used to study

Organelle other than nucleus, containing DNA is

Kitchen of the cell is

Classify the following as chemical or physical change: 

Cutting of trees

Classify the following as chemical or physical change: 

Melting of butter in a pan

Classify the following as chemical or physical change: 

Rusting of almirah

Classify the following as chemical or physical change:

Boiling of water to form steam.

Classify the following as chemical or physical change:

Passing of electric current through water, and water breaking down into hydrogen and oxygen gases.

Classify the following as chemical or physical change: 

Dissolving common salt in water.

Classify the following as chemical or physical change:

Making a fruit salad with raw fruits

Classify the following as chemical or physical change:

Burning of paper and wood