a)Ba(OH)2 + H2SO4----->BaSO4 +2H2O
b) Ta có
n\(_{B_{ }a\left(OH\right)2}=0,2.1=0,2\left(mol\right)\)
m\(_{H2SO4}=\frac{300.20}{100}=60\left(g\right)\)
n\(_{H2SO4}=\frac{60}{98}=0,61\left(mol\right)\)
=> H2SO4 dư
Theo pthh
n\(_{BaSO4}=n_{Ba\left(OH\right)2}=0,2\left(mol\right)\)
m\(_{BaSO4}=0,2.233=46,6\left(g\right)\)
c) Theo pthh
n\(_{H2SO4}=n_{Ba\left(OH\right)2}=0,2\left(mol\right)\)
n\(_{H2SO4}dư=0,61-0,2=0,41\left(mol\right)\)
mdd =300+0,2.171=334,2(g)
C%=\(\frac{0,41.98}{334,2}.100\%=1,25\%\)