The kind of twins formed from two fertilised eggs. 

Give appropriate biological / technical term

Define heat capacity and state its SI unit

Use graph paper for this question.

The marks obtained by 120 students in an English test are given below:

Draw the ogive and hence, estimate:

1. the median marks.
2. the number of students who did not pass
...

State one relevant observation: Sulphide ore is added to a tank containing oil and water, and then stirred or agitated with air.

Draw the diagram of a dual control switch when the appliance is switched ‘ON’.

What do you mean by the term - Composting.

Give a reason for the significance of irrigation in Punjab.

K, Pb, Ca, Zn. (In the increasing order of the reactivity)

Write balanced chemical equations, for the preparation of the given salts (i) to (iii) by using the methods A to C respectively:

A: Neutralization; B: Precipitation; C: Titration

1. Copper sulphate
2. Zinc
...

A gas cylinder can hold 1 kg of hydrogen at room temperature and pressure:

1. Find the number of moles of hydrogen present.
2. What weight of CO₂ can the cylinder hold under similar conditions of
...

What is meant by the term quorum?

The element with highest ionization potential is:

1. Hydrogen
2. Caesium
3. Radon
4. Helium

Give two advantages of using bio-gas as a source of power.

The removal of nitrogenous wastes from the body.

Give the Biological / technical term

Acid rain is harmful to the environment.

Name the solution used to react with Bauxite as a first step in obtaining pure aluminum oxide, in the Baeyer’s process.