15.6gC3H8*44.1gC3H8*32gO2=11.32
Answer : The volume of
required to neutralize is, 340 mL
Explanation :
To calculate the volume of base (NaOH), we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is NaOH.
We are given:

Putting values in above equation, we get:

Hence, the volume of
required to neutralize is, 340 mL
The balanced chemical formula should be Al2(SO4)3 + 6NaOH = 2Al(OH)3 + 3Na2SO4
Therefore the coefficient of Al(OH)3 is 2!
Hope that helps :)
Yes this is true as in cold conditions our body doesn't feel the urge of water therefore we may become dehydrated not even knowing about it and of course in hot coditions we sweat therefore we loose water.
Hope this helps :).