Question

I need help to evaluate if I completed my experiment calculation.

determination of water in a hydrate.
1. Mass of crucible, and cover = 18451.3
2. Mass of crucible, cover and sample = 23410.2
3. Mass of crucible, cover and sample after 1st heating = 21789.8
4. Mass of crucible, cover and sample after 2nd heating = 2116.6

I need to find the:
5. Mass of original sample & show calculation setup.
6. Total mass lost by sample during heating & show calculation setup.
7. Percentage water in sample & show water in sample & show calculation.

For # 5 I subtracted 18451.3 from 23410.2 and got 4958.9
For # 6 I subtracted 2116.6 from 4958.9 and got 2842.3.
I think the formula for #8 is % of h20 = 4958.9/2842.3 times 100, and I got 57.317 which would be 57.2.

For some reason I think that I am suppose to use some sort of formulas for question # 5 & 6. Please help me thank you.

Answer 1

I can't believe the numbers are right for all entries. For example, when I look at 23410.2-21789.6 for mass after first heating ( a loss of 1620.7) then loss after second heating of 2116.6 that's
21789.8-2116.6 = that's 19,673.2 which is unbelievable between heatings. Are you sure all of the digits are in that 2116.6 number?