How many molecules are in 10.8 grams of #C_12H_22O_11#?
The question is how many molecules are in a determined amount of an specific compound.
First step to obtain the number of moles, that is the mass/MW
#"no. of moles" = "mass"/"molar mass"#
The MW in this case is the sum of the atomic weights of the different atoms in the composition of the compound.
For this specific case it is
The number of molecules per mol is defined by the Avogadro's number
Giving up the numer of molecules as