A student investigated the temperature change that took place when different salts were dissolved in water - Edexcel - GCSE Chemistry Combined Science - Question 2 - 2023 - Paper 2

To calculate the mass of salt added to the boiling tube, we can use the masses given in Figure 4.

1. Mass of boiling tube + salt = 24.16 g
2. Mass of empty boiling tube = 22.52 g

To find the mass of the salt, we subtract the mass of the empty boiling tube from the mass of the boiling tube with salt:

$$ext{Mass of salt} = ext{Mass of boiling tube + salt} - ext{Mass of empty boiling tube}$$

Substituting the values:

$$ext{Mass of salt} = 24.16 ext{ g} - 22.52 ext{ g} = 1.64 ext{ g}$$

Thus, the mass of salt added to the water is 1.64 grams.