Question

2 C2H6 (g) + 7O2 (g)→ 4CO2 (g) + 6H2O(g) How many grams of H2O are produced from 35 L of O2 gas at STP?

Answer 1

Step-by-step explanation:

First you write the balanced chemical equation

1. 2 C2H6 + 7O2 > 4CO2 + 6H2O

Then you put X on the above of water and put 35 L on the above of O2.

35 L X

2. 2 C2H6 + 7O2 > 4CO2 + 6H2O

After that you multiply the coefficient of O2 by STD( 22.4 L ) and also H2O. And write the number on below O2 and H2O.

35 L X

3. 2 C2H6 + 7O2 > 4CO2 + 6H2O

156.7 L 134.4 L

4. Then make a proportion

`(35 \: l)/(156.8 \: l) = (x)/(134.4 \: l)`

X = 30 L

next change the volume to mole

5. 1 mol = 22.4 L

X = 30 L

X ~ 1.34

Finally change the mole to mass by the formula of:

mass of water = mole of water × molar mass of water

m = m × M

m = 1.34 mol × 18 g\mol

m = 24.12 g