If a glass is filled with 350 cm3 of water at 100°C and cools to 20°C, how much water can be added, neglecting volume expansion of the glass?

To determine how much additional water can be added to the glass after the initial 350 cm³ of water cools from 100°C to 20°C, we need to consider the contraction of the water due to cooling.

When water cools, its volume decreases. The volume contraction of water can be approximated using the coefficient of volumetric thermal expansion of water, which is about 0.00021 per degree Celsius. Given the temperature change from 100°C to 20°C, the change in temperature is 80°C.

Using the volumetric expansion formula:

[\Delta V = V_0 \cdot \beta \cdot \Delta T]

where:

• (\Delta V) is the change in volume,

• (V_0) is the initial volume (350 cm³),

• (\beta) is the coefficient of volumetric expansion, and

• (\Delta T) is the change in temperature.

Now, substituting in the values:

[\Delta V = 350 , \text{cm}^3 \cdot 0.00021 \cdot 80]

Calculating this gives:

[\Delta V \approx 5.