Q.Which of the following is/are correct for 17 g/L of H2O2 SOLUTION?
A) Volume strength is 5.6 at 273 K and 1 atm.
B) Molarity of solution is 0.5 M.
C) 1 mL of this solution gives 2.8 mL O2 at 273 K and 2 atm.
D) The normality of solution is 2 N.
(Please mark the correct answers with proper explanations.And also show the correct answer in the work.)
Volume strength of H2O2 is defined as the number of volumes of oxygen that is released on decomposition of 1 volume of a particular hydrogen peroxide solution. The decomposition follows equation:
2H2O2 (aq.) → 2H2O + O2 (g)
It follows that 68 g H2O2 produces 22400 ml O2 at STP
Therefore, 17 g H2O2 will produce 22400*68\17 = 5600 ml O2 at STP.
When 17 g H2O2 is present in 1000 ml solution, we can write
1000 ml aq. H2O2 solution produces 5600 ml O2 at STP (i.e. at 273 K and 1 atm.)
So, 1 ml aq. H2O2 solution produces 5600/1000 = 5.6 ml O2 at STP
Volume strength of 17 g/L aq. H2O2 solution is thus 5.6 volume. Option A) is correct.
Molarity of H2O2 is defined as number of moles present in 1 L solution.
Molar mass of H2O2 is 34 g
Hence 17 g/L aq. H2O2 solution is 17/34 M = 0.5 M. Option B) is correct.
Normality of H2O2 is defined as the number of gm-equivalents present in 1 L solution.
Equivalent mass of H2O2 is the mass that contains 1 g hydrogen, i.e. 34/2 = 17 g
Hence 17 g/L aq. H2O2 solution is 17/17 M = 1.0 N. Option D) is wrong.
5.6 ml O2 at STP = v ml O2 (say) at 273 K and 2 atm. pressure.
Applying gas laws,
rArr v = 5.6/2 =2.8 ml
Thus 1 ml aq. H2O2 solution produces 5.6 ml O2 at STP =2.8 ml O2 at 273 K and 2 atm. Pressure.
Option C) is also correct.
Therefore, the options A), B) and C) are correct.