What's the valency of sulphur for NaHSO4 and why?

Explanation:

According to the periodic table, it has 6 valance electrons in its outermost shell of an atom. so, the valancy must be 2.

we usually subtract the valancy from 8 to no. of electrons if no. of electrons in its outermost shell is more than 5.

so, 8-6=2

is the valancy of sulpher here.

explanation: no but i do not usually comment

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.