If a 100mL beaker weighs 5.246g and the same beaker plus 10.0 mL of water weighs 15.346g. How much does the 10.0 mL of water, alone, weigh? Show your calculation. Be sure to use significant figures.

Answer 1

The given information in the problem is that:

1. 100 mL beaker weighs 5.246g
2. 100mL beaker with 10mL weighs 15.346g

And we want to find how much does the 10mL of water weigh alone. In order to do this, we can subtract the weight of the 100mL beaker from the weight of the 100 mL beaker with 10mL in order to get just the weight of the 10 mL of water. We can do this because the weight of the 100mL beaker will cancel itself out in the equation. So, we have:

15.346g - 5.246g = 10.1 g (3 sig figs)

When you add or subtract, you assign significant figures based on the the number of decimal places in each measurement. In this case, both measurements end in the hundredths place, so we can add zeros at the end in order to make the number end in the hundredths place.

Answer:

= 10.100 (5 sig figs)

Answer 2

15.346g - 5.246g = 10.100 g