6 (a) Calculate the percentage by mass of nitrogen in ammonium nitrate, NH₄NO₃ - Edexcel - GCSE Chemistry - Question 6 - 2016 - Paper 1

To find the maximum mass of titanium that can be obtained from 500 tonnes of titanium(IV) chloride (TiCl₄), we need to use the stoichiometry of the reaction:

1. Identify the stoichiometry:

   • From the reaction: TiCl₄ + 4Na → Ti + 4NaCl, we see that 1 mole of TiCl₄ produces 1 mole of Ti.

2. Calculate the mass of 500 tonnes of TiCl₄ in kg:

   • 500 tonnes = 500,000 kg

3. Calculate the number of moles of TiCl₄:

   $\text{Number of moles of TiCl₄} = \frac{\text{mass}}{\text{molar mass}} = \frac{500,000 \text{ kg}}{190 \text{ g/mol}}$

   • Converting to grams: $500,000 \text{ kg} = 500,000,000 \text{ g}$
   • Thus, the number of moles: $\frac{500,000,000}{190} \approx 2,631,578.95 \text{ moles}$

4. Calculate the mass of titanium produced:

   • Using the molar mass of titanium (Ti = 48 g/mol): $\text{Mass of Ti} = \text{Number of moles} \times \text{molar mass} = 2,631,578.95 \text{ moles} \times 48 \text{ g} \approx 126,315,789.5 g$
   • Converting back to tonnes: $\text{Mass of titanium} \approx 126,315.79 \text{ tonnes}$

One significant problem that may arise from reactions producing unwanted products is the increase in production costs. Unwanted by-products require additional separation and purification processes, leading to increased time and resource expenditure. Moreover, the presence of these by-products might reduce the yield of the desired product, further impacting profitability. Environmental regulations related to waste disposal can also present challenges, necessitating waste treatment solutions that can add to operational costs.