Question

According to graph II, how much potassium bromide can be dissolved in 100 g of water at 40°C?

Answer 1

Based on the slope of the line between 45°C (80 g KBr/100 g water) and 90°C (100 g KBr/100 g water), the interpolation suggests approximately 77.8 g of potassium bromide can dissolve in 100 g of water at 40°C.

To determine the amount of potassium bromide (KBr) that can be dissolved in 100 grams of water at 40°C, we can interpolate based on the information provided by the graph.

1. Identify the coordinates for the relevant data points on the line:

- Point A: (45°C, 80 g KBr/100 g water)

- Point B: (90°C, 100 g KBr/100 g water)

2. Calculate the slope (m) of the line using the formula:

`\[ m = \frac{\text{Change in } y}{\text{Change in } x} = \frac{\text{(100 - 80)}}{\text{(90 - 45)}} \]`

3. Use the calculated slope to find the amount of KBr (y) dissolved in 100 grams of water at 40°C:

`\[ y - 80 = m * (40 - 45) \] \[ y = 80 + m * (-5) \]`

Substitute the calculated slope (m) into the equation to solve for y.

4. Calculate the value of y:

`\[ y = 80 - \left((20)/(45)\right) * 5 \]`

5. Solve for y to find the amount of KBr at 40°C:

`\[ y \approx 77.78 \, \text{g} \]`

Therefore, according to graph, approximately 77.78 grams of potassium bromide can be dissolved in 100 grams of water at 40°C.

The complete question is:

According to graph, how much potassium bromide can be dissolved in 100 g of water at 40°C?