Nitu presented a silver lamp to her mother on her birthday. The lamp contained 3. 011 × 1023 atoms of silver in it.

(a) Number of moles of Ca = Given mass of calcium / Molar mass of calcium = 60 / 40 = 1.5 moles  (b) Number of moles = Given number of molecules...

Weight of 1 mole of oxygen molecules = 32g of oxygen  Number of atoms in 1 mole of oxygen = 6.022 × 1023 molecules  Because 6.022 × 1023 molecules of O2 weigh...

Mass of 1 atom = 2.65 × 10−23 g  Therefore, mass of 6.022 × 1023 atoms  = 2.65 × 10−23× 6.022 × 1023 g = 15.96 g ≈ 16 g mol−1  Therefore, the atomic...

The right answer is c

To polish a gold ornament, it is dipped in a liquid called aqua regia (a mixture of hydrochloric acid and nitric acid). On getting the environment of aqua regia, the...

The silver spoon on long exposure to moist air has lost its shine and appears dull whereas gold does not tarnish.

Activities (i), (iv), (v), (vi) and (vii) can be reversed and rest cannot be reversed.

The quantity of water, salts and sugar in our body decreases when we have vomiting and loose motions. To replenish this loss a solution of sugar and salt is given.

While playing a lot of sweating occurs which causes loss of water and salt from the body. Also a lot of energy is exhausted. Since glucose solution provides instant energy,...

If Nitu had eaten the potato sabji, she might have fallen ill.