Question

A 10-mL graduate weighs 42.745 g. When 5 mL of distilled water are measured in it, the combined weight of graduate and water is 47.675 g. By definition, 5 mL of water should weigh 5 g. Calculate the weight of the measured water and express any deviation from 5 g as a percentage of error.

Answer 1

The measured weight of the water = 4.93 g

The percentage error in measured value = 1.4%

Explanation:

Given:

Weight of the 10-mL graduate = 42.745 g

Combined weight of graduate and 5 mL water = 47.675 g

5 mL of water should weight = 5 g

thus, actual value of 5 mL water = 5 g

Now,

The measured weight of the water

= (Combined weight of graduate + 5 mL water) - Weight of the 10-mL graduate

= 47.675 g - 42.745 g

= 4.93 g

The percentage error in measured value

=
`\frac{\textup{Actual value-calculated value}}{\textup{Actual value}}*100`

=
`\frac{\textup{5-4.93}}{\textup{5}}*100`

or

= 1.4%