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chemistry help please?
I need help with calculations please. Here's the info...
A sample of a pure oxide of nickel was analyzed by heating to drive off the oxygen.
Empty test tube: 32.064g
Test tube w/sample: 33.076
Pure metal and test tube after sample is heated in presence of natural gas: 32.785g
CALCULATIONS
a) mass of nickel oxide sample: I said 1.012g
b)mass of nickel present in sample: I said 0.721g
c) mass of oxygen present in original sample: I said 0.291
IF THESE ARE CORRECT, HERE IS WHERE I NEED HELP...
d) mass percent of nickel
e) mass percent of oxygen
f) find the empirical formula of the oxide of nickel
THANKS SO MUCH! BEST ANSWER IN THE MORNING :)
WON'T ALLOW ME TO DO IT YET AND I HAVE TO GET TO SLEEP.
1 Answer
- Trevor HLv 78 years agoFavorite Answer
You mass values are correct
d) mass percent of nickel
% Ni = mass of Ni / mass of original sample *100
% Ni = 0.721/1.012*100 = 71.25%
e) mass percent of oxygen
% Oxygen = 0.291/1.012*100 = 28.75%
f) find the empirical formula of the oxide of nickel
Divide mass of Ni and mass of oxygen by atomic mass
Ni = 0.721/58.7 = 0.01228
O = 0.291/16 = 0.01819
Divide by smaller value
Ni = 1
O = 0.01819/0.01228 = 1.5 ( a little rounding is permitted)
Remove fraction by multiplying by 2
Ni = 2
O = 3
Empirical formula = Ni2O3