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posledela
3 years ago
7

Please help me out!!!

Chemistry
2 answers:
noname [10]3 years ago
6 0
What subject is this ?
marta [7]3 years ago
3 0
Normally these questions ask for the empirical formula of the compound. You want mass%, so you get mass%:
Mass C in 7.93mg CO2
Molar mass CO2 = 12.011+15.999*2 = 44.009g/mol
Molar mass C = 12.011
Mass C = 12.011/44.009*7.93 = 2.1643mg C

Mass H in 4.87mg H2O
Molar mass H2O = 1.008*2+15.999 = 18.015g/mol
Molar mass H2 = 1.008*2 = 2.016
Mass H in 4.87mg H2O = 2.016/18.015*4.87 = 0.545mg H

Mass O = 5.59 -(2.1643 + 0.545) = 2.8807mg

% mass composition:
C = 2.1643/5.59*100 = 38.71%
H = 0.545/5.59*100 = 9.750%
O = 2.880/5.59*100 = 51.52%
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Answer:

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Explanation:

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Next, we shall convert the pressure and temperature to appropriate units. This is illustrated below:

For Pressure:

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For Temperature:

T(K) = T(°C) + 273

T(°C) = 28°C

T(K) = 28°C + 273 = 301K.

Next we shall determine the volume of N2. The volume of N2 can be obtained by using the ideal gas equation as shown below:

PV = nRT

Pressure (P) = 0.98 atm

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Gas constant (R) = 0.0821atm.L/Kmol.

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V = 0.378 L

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