Respuesta :
Answer is c
Work out the moles of 2H2O: 1.80/ (16+1+1) = 0.1
The moles of 2H2 are the same (0.1)
The Mr of H2 is 2
So the mass needed to produce 1.80g of water is
0.1 x 2 = 0.2
Work out the moles of 2H2O: 1.80/ (16+1+1) = 0.1
The moles of 2H2 are the same (0.1)
The Mr of H2 is 2
So the mass needed to produce 1.80g of water is
0.1 x 2 = 0.2
Answer : The correct option is, (C) 0.200 g
Explanation : Given,
Mass of water = 1.80 g
Molar mass of water = 18 g/mole
Molar mass of [tex]H_2[/tex] = 2 g/mole
First we have to calculate the moles of water.
[tex]\text{Moles of }H_2O=\frac{\text{Mass of }H_2O}{\text{Molar mass of }H_2O}=\frac{1.80g}{18g/mole}=0.1mole[/tex]
Now we have to calculate the moles of hydrogen gas.
The given balanced reaction is,
[tex]2H_2+O_2\rightarrow 2H_2O[/tex]
From the balanced reaction we conclude that
As, 2 mole of water obtained from 2 mole of [tex]H_2[/tex] gas
So, 0.1 mole of water obtained from 0.1 mole of [tex]H_2[/tex] gas
Now we have to calculate the mass of hydrogen gas.
[tex]\text{Mass of }H_2=\text{Moles of }H_2\times \text{Molar mass of }H_2[/tex]
[tex]\text{Mass of }H_2=(0.1mole)\times (2g/mole)=0.2g[/tex]
Therefore, the mass of hydrogen gas required will be, 0.2 grams
