A o.8378g sample of calcium oxalate is heated to 1000°C.(a) calculate the moles of CaO remaining after ignition .(b)calculate the millimoles of CO evolved. (C) Calculate the weight of CO2 produced.
Stepwise:
CaC2O4 (s) → CaCO3 s + CO (g)
CaCO3(s) ==> CaO(s) + CO2(g)
Total reaction:
CaC2O4 ==> CaO + CO + CO2
mols CaC2O4 = grams/molar mass = 0.8378/128 = 0.00654
Notice 1 mol CaC2O4 produces 1 mjol CO2 and 1 mol CO so
0.00654 mola CaC2O4 will produce 0.00654 mols CO and 0.00654 mols CO2.
mllimols CO = mols CO x 1000 = ?
mass CO2 = mols CO2 x molar mass CO2 = ?
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To solve this problem, we first need to determine the balanced equation for the reaction of calcium oxalate (CaC2O4) when heated to 1000°C.
The balanced equation for the reaction is as follows:
CaC2O4 (s) --> CaO (s) + 2CO (g)
Now we can proceed with the calculations:
(a) Calculating the moles of CaO remaining after ignition:
1. Calculate the molar mass of CaC2O4:
Ca: 1 atom x 40.08 g/mol = 40.08 g/mol
C: 2 atoms x 12.01 g/mol = 24.02 g/mol
O: 4 atoms x 16.00 g/mol = 64.00 g/mol
Total molar mass = 40.08 g/mol + 24.02 g/mol + 64.00 g/mol = 128.10 g/mol
2. Convert the given sample mass from grams (g) to moles (mol):
Mass of sample = 0.8378 g
Moles of CaC2O4 = Mass of sample / Molar mass of CaC2O4
Moles of CaC2O4 = 0.8378 g / 128.10 g/mol = 0.00653 mol
3. From the balanced equation, we can see that the molar ratio between CaC2O4 and CaO is 1:1.
Therefore, the number of moles of CaO remaining after ignition is also 0.00653 mol.
(b) Calculating the millimoles of CO evolved:
From the balanced equation, we can see that the molar ratio between CaC2O4 and CO is 2:1.
Therefore, the number of moles of CO evolved is half the number of moles of CaC2O4.
Moles of CO evolved = 0.00653 mol / 2 = 0.00327 mol
To convert moles to millimoles, multiply by 1000:
Millimoles of CO evolved = 0.00327 mol x 1000 = 3.27 mmol
(c) Calculating the weight of CO2 produced:
From the balanced equation, we can see that the molar ratio between CaC2O4 and CO2 is 1:1.
Therefore, the number of moles of CO2 produced is equal to the number of moles of CaC2O4.
Moles of CO2 produced = 0.00653 mol
The molar mass of CO2 is:
C: 1 atom x 12.01 g/mol = 12.01 g/mol
O: 2 atoms x 16.00 g/mol = 32.00 g/mol
Total molar mass = 12.01 g/mol + 32.00 g/mol = 44.01 g/mol
Weight of CO2 produced = Moles of CO2 produced x Molar mass of CO2
Weight of CO2 produced = 0.00653 mol x 44.01 g/mol = 0.287 g
Therefore, the weight of CO2 produced after ignition is 0.287 grams.
To answer these questions, we need to use stoichiometry, which involves balancing chemical equations and determining the molar ratios between reactants and products.
The balanced chemical equation for the combustion of calcium oxalate (CaC2O4) is:
2 CaC2O4 → 2 CaO + 4 CO + CO2
(a) To calculate the moles of CaO remaining after ignition, we need to determine the moles of CaC2O4 and then apply the stoichiometric ratio.
First, we calculate the moles of CaC2O4:
Molar mass of CaC2O4 = atomic mass of Ca + 2 * atomic mass of C + 4 * atomic mass of O
= 40.08 g/mol + 2 * 12.01 g/mol + 4 * 16.00 g/mol
= 128.08 g/mol
Moles of CaC2O4 = mass of sample / molar mass
= 0.8378 g / 128.08 g/mol
Now, we apply the stoichiometric ratio between CaC2O4 and CaO:
1 mole CaC2O4 = 1 mole CaO
So, the moles of CaO remaining would be the same as the moles of CaC2O4.
(b) To calculate the millimoles of CO evolved, we need to determine the moles of CaC2O4 and then apply the stoichiometric ratio between CO and CaC2O4.
First, we need to calculate the moles of CaC2O4 using the same method as in part (a).
Now, we apply the stoichiometric ratio between CO and CaC2O4:
1 mole CaC2O4 = 4 moles CO
So, the moles of CO evolved would be the moles of CaC2O4 multiplied by 4.
To convert moles to millimoles, multiply by 1000.
(c) To calculate the weight of CO2 produced, we need to determine the moles of CaC2O4 and then apply the stoichiometric ratio between CO2 and CaC2O4.
First, we need to calculate the moles of CaC2O4 using the same method as in part (a).
Now, we apply the stoichiometric ratio between CO2 and CaC2O4:
1 mole CaC2O4 = 1 mole CO2
So, the moles of CO2 produced would be the same as the moles of CaC2O4.
To convert moles to weight, we multiply by the molar mass of CO2:
Molar mass of CO2 = atomic mass of C + 2 * atomic mass of O
= 12.01 g/mol + 2 * 16.00 g/mol
= 44.01 g/mol
Weight of CO2 produced = moles of CO2 * molar mass of CO2