The fizz produced when an antacid dissolves in water is caused by the reaction between sodium hydrogen carbonate (NaHCO3) and citric acid (H3C6H5O7). The balanced equation for the reaction is:
3NaHCO3(aq) + H3C6H5O7(aq) → Na3C6H5O7(aq) + 3CO2(g) + 3H2O(ℓ)
5.1 Write down the FORMULA of the substance that causes the fizz when the antacid dissolves in water. (1)
A certain antacid contains 1,8 g of H3C6H5O7 and 3,36 g of NaHCO3. The antacid is dissolved in 100 cm3 distilled water in a beaker.
5.2 Define 1 mole of a substance. (2)
5.3 Calculate the number of moles of NaHCO3 in the antacid. (3)
5.4 Determine, using calculations, which substance is the limiting reagent. (4)
5.5 Calculate the mass of the reactant in excess. (3)
5.6 Calculate the mass decrease of the beaker contents on completion of the reaction. (3)
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