Matter in Our Surroundings — Science STD 9 — Question

‘X’ and ‘Y' are two elements which form X₂Y₃ and X₃Y₄. If 0.2mol of X₂Y₃ weighs 32g and 0.4mol of X₃Y₄, weighs 92.8g, the atomic weights of X and Y respectively are:

Rutherford’s alpha particle scattering experiment led to the discovery of:

An atom is:

An earthenware keeps water cool but a metallic vessel does not because:

Change in the state of matter can be brought by changing :

Which one of the following set of phenomena would increase on raising the temperature?

1. Diffusion, evaporation, compression of gases.
2. Evaporation, compression of gases, solubility.
3. Evaporation, diffusion, expansion of gases.
4. Evaporation, solubility, diffusion, compression of gases.

The radioactive isotope used in the treatment of cancer is:

The cation of an element has:

1. The same number of electrons as its neutral atom.
2. More electrons than a neutral atom.
3. Less protons than a neutral atom.
4. Less electrons than a neutral atom.

Cathode rays have:

When two molecules of hydrogen react with one molecule of oxygen, the mass of reactants is 36, what is the mass of products: