Work And Energy — Science STD 9 — Question

Which of the following substance cannot be broken down by a chemical method?

Water molecules move from their ______ concentration to their ______ concentration during osmosis:

If the displacement of an object is proportional to the square of time, then the object is moving with:

The structure of nuclear membrane is suitable for:

Choanocytes are unique to:

1. Protozoa.
2. Porifera.
3. Mollusca.
4. Echinodermata.

Two elements X and Y have valencies of 5 and 3, and 3 and 2, respectively. The elements X and Y are most likely to be respectively:

Cells which lose their nucleus during differentiation are:

Pulses such as pea and gram are good sources of:

Which one of the following statements is not true?

1. The molecules in a solid vibrate about a fixed position.
2. The molecules in a liquid are arranged in a regular pattern.
3. The molecules in a gas exert negligibly small forces on each other, except during collisions.
4. The molecules of a gas occupy all the space available.

The law of constant phosphorus, sulphur and krypton, the elements having the lowest and highest atomicities are respectively: