how many grams of solid d will mix in 250 grams of water at 40°c? (rounded to the nearest whole number)

Explanation:

Step1: Determine solubility at 40°C

From the graph, the solubility of solid D at 40°C is 40 g per 100 g of water.

Step2: Set up proportion

Let $x$ be the mass of solid D in 250 g of water. The proportion is $\frac{40}{100}=\frac{x}{250}$.

Step3: Solve for x

Cross - multiply: $100x = 40\times250$. Then $x=\frac{40\times250}{100}$. $x = 100$.

Answer:

100