Please solve 5th and 6th question.

Dear student,

5) The total number of aoms in K2Cr2O7 is,
2 + 2 + 7 = 11
S exist as S8 in Nature and hence its atomicity is 8.
Hence the correct answer is 11 & 8.

6) Molar mass of Na2CO3 is,
23 x 2 + 12 + 3 x 16 = 46 + 12 + 48 = 106
Molar mass of H2SO4 is,
2 x 1 + 32 + 4 x 16 = 2 + 32 + 64 = 98.
Hence the correct option is c.

Regards