Explanation:
For a compound to show hydrogen bonding it is necessary that the hydrogen atom of the compound should be attached to more electronegative atom like fluorine, oxygen or nitrogen.
For example, ,
and
all these compounds contain an electronegative atom attached to hydrogen atom.
Therefore, these pure compounds will exhibit hydrogen bonding.
Thus, we can conclude that out of the given options ,
and
are the pure compounds which will exhibit hydrogen bonding.
The concentration of solution in M or mol/L can be calculated using the following formula:
.... (1)
Here, n is number of moles and V is volume of solution in L.
The molecular formula of potassium sulfate is thus, there are 2 moles of potassium in 1 mol of potassium sulfate.
1 mol of potassium will be there in 0.5 mol of potassium sulfate.
Mass of potassium is 4.15 g, molar mass is 39.1 g/mol.
Number of moles can be calculated as follows:
Here, m is mass and M is molar mass
Putting the values,
Thus, number of moles of will be
.
The volume of solution is 225 mL, converting this into L,
Thus,
Putting the values in equation (1),
Therefore, concentration of potassium sulfate solution is 0.236 M.