Answer:
Five
Explanation:
All group 15 elements have five valence electrons, but they vary in their reactivity.
Can you use a calculator? If so, demos works great for problems like these!
Answer:
1. Balanced chemical for the given chemical reaction is :

number of mole of sulphuric acid produced = 12.5 mol
number of mole of oxygen required=6.25 mol
Explanation:
1. Balanced chemical for the given chemical reaction is :

from above balanced equation it is clearly that ,
2 mole of sulpher dioxide gives 2 mole of sulphuric acid
1 mole of sulpher dioxide gives 1 mole of sulphuric acid
therefore,
12 .5 mole of sulpher dioxide will givs 12.5 mole of sulphuric acid
number of mole of sulphuric acid produced = 12.5 mol
2 mole of sulphur dioxide needs 1 mole of oxygen gas
so,
1 mole of sulphur dioxide needs 0.5 mole of oxygen gas
therefore 12.5 of sulphur dioxide needs
mole of oxygen
number of mole of oxygen required=6.25 mol
A process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one thus equalizing the concentrations on each side of the membrane. I hope this helps :D