Question

Acetylene gas (C2H2) is produced as a result of the reaction CaC2(s) + 2 H2O(ℓ) → C2H2(g) + Ca(OH)2(aq). If 10 g of CaC2 are consumed in this reaction, how much H2O is needed? Answer in units of mol.

Answer 1

To find the amount of H2O needed in the reaction CaC2(s) + 2 H2O(l) -> C2H2(g) + Ca(OH)2(aq), we can use stoichiometry. The balanced equation shows that 1 mole of CaC2 reacts with 2 moles of H2O to form 1 mole of C2H2.

Step-by-step explanation:

To find the amount of H2O needed in the reaction CaC2(s) + 2 H2O(l) -> C2H2(g) + Ca(OH)2(aq), we can use stoichiometry. The balanced equation shows that 1 mole of CaC2 reacts with 2 moles of H2O to form 1 mole of C2H2. We know that 10 g of CaC2 is consumed in the reaction, so we need to find the amount of H2O in moles that corresponds to that amount of CaC2. To do this, we can use the molar mass of CaC2 to convert grams to moles. Once we have the moles of CaC2, we can use the mole ratio from the balanced equation to find the moles of H2O needed.

The molar mass of CaC2 is 64.1 g/mol. So, 10 g of CaC2 is equal to 10/64.1 = 0.156 moles. Using the mole ratio from the balanced equation, we can determine that 0.156 moles of CaC2 requires 0.156 x 2 = 0.312 moles of H2O.

Answer 2

The answer to your question is 0.32 moles of water are needed.

Step-by-step explanation:

Data

mass of CaC₂ = 10 g

mass of water = ?

Process

1.- Write the balanced reaction

CaC₂ + 2H₂O ⇒ C₂H₂ + Ca(OH)₂

Reactant Element Product

1 Ca 1

2 C 2

4 H 4

2 O 2

The reaction is balanced

2.- Convert mass of CaC₂ to moles

molecular mass CaC₂ = 40 + (2 x 12)

= 40 + 24

= 64 g

64 g of CaC₂ ----------------- 1 mol

10 g ----------------- x

x = (10 x 1) / 64

x = 10/64

x = 0.16 moles of CaC₂

3.- Calculate the moles of water

1 mol of CaC₂ ----------------- 2 moles of water

0.16 moles of CaC₂ --------- x

x = (0.16 x 2) / 1

x = 0.32 moles of water