Question

Consider the reaction between acetylene, c2h2, and oxygen in a welding torch: 2c2h2(g) + 5o2(g) → 4co2(g) + 2h2o(g) if 5.4 moles of acetylene react with sufficient oxygen, how many grams of co2 will be formed?

a. 2.4 × 102 g
b. 9.5 × 102 g
c. 4.8 × 102 g
d. 1.5 × 102 g
e. 0.49 g

Answer 1

2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O(g)
from the reaction 2 mol 4 mol
from the problem 5.4 mol 10.8 mol

M(CO2) = 12.0 +2*16.0 = 44.0 g/mol
10.8 mol CO2 * 44.0 g CO2/1 mol CO2 = 475.2 g CO2 ≈480 = 4.8 * 10² g
Answer is C. 4.8*10² g.

Answer 2

Answer : The mass of
`CO_2` formed will be,
`4.8* 10^2g`

Explanation :

The balanced chemical reaction will be:

`2C_2H_2(g)+5O_2(g)\rightarrow 4CO_2(g)+2H_2O(g)`

First we have to calculate the moles of
`CO_2`.

From the reaction, we conclude that

As, 2 mole of
`C_2H_2` react to give 4 mole of
`CO_2`

So, 5.4 moles of
`C_2H_2` react to give
`(4)/(2)* 5.4=10.8` moles of
`CO_2`

Now we have to calculate the mass of
`CO_2`

`\text{ Mass of }CO_2=\text{ Moles of }CO_2* \text{ Molar mass of }CO_2`

`\text{ Mass of }CO_2=(10.8moles)* (44g/mole)=475.2g=4.8* 10^2g`

Therefore, the mass of
`CO_2` formed will be,
`4.8* 10^2g`