I came across this question:

A quantity of electrical charge that brings about the deposition of 4.5 g $\ce{Al}$ from $\ce{Al^{+3}}$ at cathode will also produce the following volume (STP) of $\ce{H2}$ (g) from $\ce{H+}$ at cathode:

A)22.4

B)11.2

C)5.6

D)2.8

If we use faradays first law: For $\ce{Al^{+3}}$

4.5-=(27*c)/ (96500*3)

c=96500/2

For $\ce{H2}$:

m=c/(96500*2)

m=0.25

Hence V=2.8

If we use 2nd law, we get mass of $\ce{H2}$ produced as 0.5 Hence, V=5.6

So then what was the mistake (Please reply if I have made calculation mistake, I generally do that)