Conservation Of Mass And Balanced Chemical Equations (GCSE Chemistry)

What is the empirical formula of a compound that is 40.0% C, 6.7% H, 53.3% O by mass (approx)?

A solution contains 0.100 mol of HCl in 250 cm3. What is the concentration in mol/dm3?

A gas occupies 24.0 dm3 at room temperature and pressure (RTP). How many moles of gas does it contain?

Which statement best describes the law of conservation of mass in a chemical reaction?

If 0.250 mol of NaCl is dissolved in enough water to make 0.500 dm3 of solution, what is the concentration in mol/dm3?

A reaction A + B ? C is found to produce 30.0 g of product C from 50.0 g total starting mass of A + B in a closed system with no mass lost. How much mass of unreacted material remains in the container after reaction?

Balance the redox equation by inspection: Fe2O3 + C ? Fe + CO. The coefficient for C is:

A student obtains 8.0 g of product when the theoretical maximum was 10.0 g. Which statement is correct?

At RTP 1 mole of any gas occupies 24.0 dm3. If 48.0 dm3 of oxygen is collected, how many moles is that?

If 10.0 g of magnesium react with excess hydrochloric acid to form magnesium chloride and hydrogen, the mass of hydrogen produced (approximately) is closest to:

When 2.00 mol of hydrogen reacts completely with 1.00 mol of oxygen to form water, what mass (g) of water is produced? (Mr H2O = 18.0)