Moles of calcium metal used = 100/40.1=2.5
Moles of HBr need to react = 5 moles
As the molar ratio is 1 is to 2 among them
so
Moles=molarity x volume
5=2.25 x volume
volume=2.22 litres of HBr required for this reaction
ANSWER IS 2.22 LITRES
The balanced equation for the reaction between KOH and HBr is as follows;
KOH + HBr --> KBr + H₂O
stoichiometry of KOH to HBr is 1:1
number of KOH moles reacted - 0.25 mol/L x 0.015 L = 0.00375 mol
according to molar ration
number of KOH moles reacted = number of HBr moles reacted
number of HBr moles reacted - 0.00375 mol
if 12 mL of HBr contains - 0.00375 mol
then 1000 mL of HBr contains - 0.00375 mol / 12 mL x 1000 mL = 0.313 mol
therefore molarity of HBr is 0.313 M
Correct answer: Option D, <span>
K = 5.04 × 10^52</span>
Reason:
We know that,
Ecell =

,
where n = number of electrons = 2 (in present case)
K = equilibrium constant.
Also, Ecell = <span>+1.56 v
Therefore, 1.56 = </span>

Therefore, log (K) = 52.703
Therefore, K = 5.04 X 10^52
D water expands when it freezes