Question

3.42g of sucrose contains_number of carbon atioms

Answer 1

mole of sucrose = 3.42/342 = 0.01
number of atom of sucrose = 6.02×10∧23*0.01 = 6.02×10∧21
one sucrose atom contain 12 carbon atom
so number of carbon atom in 3.42g of sucrose = 12×6.02×10∧21
                                                                   = 72.24×10∧21

Answer 2

the formula for sucrose is C12 H22 O11 hence the atomic weight is

 ( 12*12 + 22 *1 + 16*11)  =  342 g

           342 g  which will have 12 carbon atoms

hence  3.42 g  will have  --------------------->      (  3.42 * 12 )  / 342  = 0. 12 atoms