Is Matter Around Us Pure ? — Science STD 9 — Question

Crude oil is purified using fractional distillation process. This method works on the principle of:

Interfascicular cambium is an example of-

If suddenly the gravitational force of attraction between earth and satellite revolving around it becomes zero, then the satellite will

The time taken to complete one oscillation is called.

The atomic number of an element X is 8 and that of element Y is 4. Both these elements can exhibit a valency of:

The relative densities of four liquids P, Q, R and S are 1.26, 1.0, 0.84 and 13.6 respectively. An object is floated in all these liquids, one by one. In which liquid the object will float with its maximum volume submerged under the liquid?

1. P
2. Q
3. R
4. S

When a gas jar containing colourless air is kept upside down over a gas jar full of brown-coloured bromine vapour, then after sometime, the brown colour of bromine vapour spreads into the upper gas jar making both the gas jars appear brown in colour. Which of the following conclusion obtained from these observations is incorrect?

In a eukaryotic cell, the nucleus has:

The sound waves travel fastest:

1. In solids.
2. In liquids.
3. In gases.
4. In vacuum.

Which of the following are chemical changes?

1. Decaying of wood.
2. Burning of wood
3. Sawing of wood
4. Hammering of nail into wood