What is the minimum percentage of gas (C2H2) formed when 2.66g of calcium carbide (CaC2) reacts completely with 50g water?

CaC2+2H2O -> C2H2+ Ca(OH)2

Percent of gas? is there another gas present?

percent of gas

Percent of gas

To find the minimum percentage of gas (C2H2) formed, we need to determine the amount of C2H2 produced and compare it to the total mass of reactants.

1. Calculate the molar masses:
- The molar mass of CaC2 is 64.1 g/mol. (1 calcium atom with a mass of 40.1 g/mol + 2 carbon atoms with a mass of 12.0 g/mol)
- The molar mass of H2O is 18.0 g/mol. (2 hydrogen atoms with a mass of 1.0 g/mol each + 1 oxygen atom with a mass of 16.0 g/mol)
- The molar mass of C2H2 is 26.0 g/mol. (2 carbon atoms with a mass of 12.0 g/mol each + 2 hydrogen atoms with a mass of 1.0 g/mol each)

2. Determine the number of moles of CaC2 and H2O:
- The number of moles of CaC2 can be calculated by dividing the given mass (2.66 g) by its molar mass (64.1 g/mol).
- The number of moles of H2O can be calculated by dividing the given mass (50 g) by its molar mass (18.0 g/mol).

3. Determine the limiting reactant:
- The balanced chemical equation indicates that 1 mole of CaC2 reacts with 2 moles of H2O to form 1 mole of C2H2.
- Compare the moles of CaC2 and H2O. The reactant with the smaller number of moles is the limiting reactant, as it determines how much product can be formed.

4. Calculate the moles of C2H2 formed:
- Since the limiting reactant is CaC2, there will be an equal number of moles of C2H2 produced.
- Multiply the moles of CaC2 by the stoichiometric ratio, which is 1 mole of C2H2 per 1 mole of CaC2.

5. Calculate the mass of C2H2 formed:
- Multiply the moles of C2H2 formed (calculated in step 4) by the molar mass of C2H2 (26.0 g/mol) to get the mass.

6. Calculate the minimum percentage of C2H2 formed:
- Divide the mass of C2H2 formed (calculated in step 5) by the total mass of the initial reactants (mass of CaC2 + mass of H2O), and multiply by 100 to get the percentage.
- Note that the mass of Ca(OH)2 formed and any unreacted CaC2 will not contribute to the mass of C2H2 formed.

By following these steps, you should be able to find the minimum percentage of C2H2 gas formed in the reaction between CaC2 and H2O.