Chemistry Past Questions and Answers

0.499g 0f CuSO<sub style='font-size: smaller;'>4</sub>.xH<sub style='font-size: smaller;'>2</sub>O when heated to constant weight gave a residue of 0.346g. the value of x is? (Cu = 63.5, S = 32.0, O = 16, H = 1)

In the experiment, which of the following observations would suggest that a solid sample is a mixture? The

Hydrogen diffuses through a porous plug

Given that the molecular mass of iron is 56 and that of oxygen is 16, how many moles of iron(iii)oxide will be contained in 1kg of the compound?

3.0g of a mixture of potassium carbonate and potassium chloride were dissolved in a 25cm<sup style='font-size: smaller;'>3</sup> of this solution required required 40.00cm<sub style='font-size: smaller;'>3</sub> of 0.1M HCl for neutralization. What is the percentage by weight of K<sub style='font-size: smaller;'>2</sub>CO<sub style='font-size: smaller;'>3</sub> in the mixture. (K = 39, O = 16, C = 12)