What mass of na2co3 is present in 0.650 l of a 0.505 m na2co3 solution?

V=0.650 L
c=0.505 mol/L
M(Na₂CO₃)=106.0 g/mol

the amount of substance of sodium carbonate is:
n(Na₂CO₃)=vc

the mass of sodium carbonate is:
m(Na₂CO₃)=n(Na₂CO₃)M(Na₂CO₃)

m(Na₂CO₃)=vcM(Na₂CO₃)

m(Na₂CO₃)=0.650*0.505*106.0=34.7945 g

The independent variable is the type of music.the dependent variable is the pulse rate.the intervening variable is the age of the subject.if the mother does not like rock, her pulse is likely to not increase.the same might be true for the sister.the friend may like rap and gets excited.to establish cause/effect relationship, all of the subjects must be consistent.hope i .