Atoms and Molecules — Science STD 9 — Question

Symbol of ______ is taken from Greek word Kalium.

If the temperature of an object is 268K, it will be equivalent to:

1. -5°C
2. +5°C
3. 368°C
4. -25°C

Who stated the law of constant proportion:

In which of the following, dispersed phase is a liquid while dispersion medium is a gas:

Number of valence electrons present in N^3- ion is:

Which is more effective in cooling:

The amount of energy required to change 1 kg of a solid into liquid at atmospheric pressure at its melting point is known as _______________?

The molecular formula of potassium nitrate is ________.

Elements having valency ‘one’ are:

1. Always metals.
2. Always non-metals.
3. Always metalloids.
4. Either metals or non-metals.