Physical and Chemical Changes Separation of a Mixture Mass of evaporating dish + watch glass=273.5g

Mass of evaporating dish, watch glass + sample=278.5g

Mass of sample=5.0g

Determining percent of NaCl in mixture:

Mass of evaporating dish, watch glass, and solids(after water washes)=286.1g

Mass of NaCl=

Percent of NaCl in unknown=

Determining Percent of CaCO3 in mixture:

Mass of dish, watch glass, and SiO2( final weighing)=239.2

Mass of CaCO3=

Percent of CaCO3 in unknown=

Determining a Percent of SiO2 in mixture:

Mass of SiO2=

Percent of SiO2 in unknown=

I really don't understand how to math all of the stuff so if you could also provide how to solve it, that would be helpful!