Part A) Based on the following data, complete the table below as if you were mak
ID: 477771 • Letter: P
Question
Part A) Based on the following data, complete the table below as if you were making the calculations described in the lab. Formula of Anhydrous Salt (supplied by instructor) CuSO4 Mass of Crucible 26.30 g Mass of Crucible + Hydrate 29.95
What is the mass of Hydrate in grams?
Answer: 3.65 g
Part B) You dry the hydrate as instructed in the lab procedure, noting down it's mass until it appears to no longer decrease (no more water bound in the sample). Mass of Salt + Crucible (after 1st heating) 28.69 Mass of Salt + Crucible (after 2nd heating) 28.63
What is the Mass of Salt after second heating (ie. dry CuSO4)?
Answer: ? g
Part C) So what is the Mass of Water (liberated during drying)?
Answer: ? g
Part D) How many Moles of Anhydrous Salt is this (moles of CuSO4)?
answer: ? moles
Part E) How many Moles of Water were in the sample (liberated during heating)?
Answer: ? moles
Part F) So what is the Empirical Formula of this salt hydrate?
a) CuSO4 ·1H2O
b) CuSO4 ·2H2O
c) CuSO4 ·5H2O
d) CuSO4 ·7H2O
Explanation / Answer
b] Mass of salt after second heating = Mass of Hydrate - Mass of H2O = 3.65 - 1.32 = 2.33
c] Mass of H2O =
Mass of hydrate + crucible- Mass of salt after second heating + crucible = 29.95 - 28.63 = 1.32 gms
d] Moles = Mass / MW
MW of CusO4 = 160
Moles = 2.33 / 160 = 0.0145625
e] Moles = Mass / MW = 1.32 / 18 = 0.0733
f]
Moles of H2O /Moles of CuSO4 = 0.0733 / 0.0145625 = 5
Formula is CuSO4.5H2O