If you have 20 mL of pure water at room temperature, what is its mass in grams?

• A. 0.2 g
• B. 20 g
• C. 2 g
• D. 200 g

Answer: (B)

Verified step by step guidance

1. Identify the physical property that relates volume and mass for water, which is its density. At room temperature, the density of pure water is approximately 1 g/mL.
2. Write down the formula that relates mass, volume, and density: \(\text{mass} = \text{density} \times \text{volume}\).
3. Substitute the known values into the formula: density = 1 g/mL and volume = 20 mL.
4. Calculate the mass by multiplying the density by the volume: \(\text{mass} = 1 \frac{g}{mL} \times 20 \ mL\).
5. Interpret the result as the mass of the water in grams, which corresponds to the volume given.