Draw and label the axes. The x-axis should represent Temperature (^ C) and the y-axis should represent Solubility (g/100g of water).

a) To plot the graph of solubility of potassium nitrate against temperature: Step 1: Draw and label the axes. The x-axis should represent Temperature (^ C) and the y-axis should represent Solubility (g/100g of water). Step 2: Choose an appropriate scale for each axis. • For the x-axis (Temperature): A suitable scale would be 1 cm (or 1 major grid square) representing 10^ C. This allows the temperature range from 10^ C to 100^ C to fit well. • For the y-axis (Solubility): A suitable scale would be 1 cm (or 1 major grid square) representing 10 g/100g of water. Start the y-axis at a value like 70 g/100g of water to accommodate the lowest solubility value of 80 g/100g of water. Step 3: Plot the given data points from the table onto the graph paper. For example, plot (10, 80), (20, 88), (30, 96), and so on, up to (100, 180). Step 4: Draw a smooth curve through the plotted points. This curve represents the solubility curve for potassium nitrate. b) From the graph, determine: (Note: Since a physical graph cannot be plotted here, the values are determined by interpolation from the given data, which is equivalent to reading from a well-drawn graph.) i) The solubility of potassium nitrate at 65^ C. Step 1: Locate 65^ C on the temperature (x-axis). Step 2: Draw a vertical line from 65^ C up to the solubility curve. Step 3: From the point where the vertical line intersects the curve, draw a horizontal line to the solubility (y-axis). Based on interpolation between 60^ C (124 g/100g water) and 70^ C (136 g/100g water): Solubility at 65^ C = 124 + (65-60)/(70-60) × (136-124) = 124 + (5)/(10) × 12 = 124 + 0.5 × 12 = 124 + 6 = 130 g/100g of water The solubility of potassium nitrate at 65^ C is 130 g/100g of water. ii) The mass of potassium nitrate that would dissolve in 50 g of water at 82^ C. Step 1: Determine the solubility at 82^ C from the graph. Based on interpolation between 80^ C (148 g/100g water) and 90^ C (162 g/100g water): Solubility at 82^ C = 148 + (82-80)/(90-80) × (162-148) = 148 + (2)/(10) × 14 = 148 + 0.2 × 14 = 148 + 2.8 = 150.8 g/100g of water This means 150.8 g of potassium nitrate dissolves in 100 g of water at 82^ C. Step 2: Calculate the mass that dissolves in 50 g of water. Since 50 g of water is half of 100 g of water, the mass of potassium nitrate that dissolves will also be half. Mass of KNO_3 = 150.8 g100 g water × 50 g water = (150.8)/(2) g = 75.4 g The mass of potassium nitrate that would dissolve in 50 g of water at 82^ C is 75.4 g. 3 done, 2 left today. You're making progress.