Force and Laws of Motion — Science STD 9 — Question

Two chemical substances X and Y combine together to form a product P which contains both X and Y
X + Y → P
X and Y cannot be broken down into simpler substances by simple chemical reactions. Which of the following statements concerning X, Y and P are correct?

1. P is a compound.
2. X and Y are compound.
3. X and Y are elements.
4. P has a fixed composition.

1. (i), (ii) and (iii)
2. (i), (ii) and (iv)
3. (ii), (iii) and (iv)
4. (i), (iii) and (iv)

The phenomenon of change of a liquid into the gaseous state at any temperature below its boiling point is called:

Which of the following statements given below is correct about meristematic tissue?

Which of the following was not proposed by Thomson?

The size of most of the cells is best expressed in:

A particle X has 17 protons, 18 neutrons and 18 electrons. This particle is most likely to be:

1. A cation.
2. An anion.
3. A molecule.
4. A compound.

The evaporation of water increases under the following conditions:

1. Increase in temperature, decrease in surface area.
2. Increase in surface area, decrease in temperature.
3. Increase in surface area, rise in temperature.
4. Increase in temperature, increase in surface area, addition of common salt.

Four balls, A, B, C and D displace 10mL, 24mL, 15mL and 12mL of a liquid respectively, when immersed completely. The ball which will undergo the maximum apparent loss in weight will be:

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

Select the most appropriate option.Eukaryotic cells have a dense double membrane-bound structure inside, called: