Pressure does not affect the voltage produced in a voltaic cell.
Explanation:
Let us assume that total mass of the solution is 100 g. And, as it is given that acetic acid solution is 12% by mass which means that mass of acetic acid is 12 g and 88 g is the water.
Now, calculate the number of moles of acetic acid as its molar mass is 60 g/mol.
No. of moles =
= 
= 0.2 mol
Molarity of acetic acid is calculated as follows.
Density = 
1 g/ml = 
volume = 100 ml
Hence, molarity = 
= 
= 2 mol/l
As reaction equation for the given reaction is as follows.

So, moles of NaOH = moles of acetic acid
Let us suppose that moles of NaOH are "x".
(as 1 L = 1000 ml)
x = 20 L
Thus, we can conclude that volume of NaOH required is 20 ml.
Answer: The balanced equation is
.
Explanation:
The given reaction equation is as follows.

Number of atoms present on reactant side are as follows.
- Li = 1
- H = 1
= 1
Number of atoms present on product side are as follows.
- Li = 1
- H = 2
= 1
To balance this equation, multiply Li by 2 and
by 2 on reactant side. Also, multiply
by 2 on product side.
Hence, the equation can be rewritten as follows.

Now, number of atoms present on reactant side are as follows.
- Li = 2
- H = 2
= 2
Number of atoms present on product side are as follows.
- Li = 2
- H = 2
= 2
As there are same number of atoms on both reactant and product side. Hence, the equation is now balanced.
Thus, we can conclude that the balanced equation is
.