\(a,n_{CO_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\\ Ba\left(OH\right)_2+CO_2\rightarrow BaCO_3+H_2O\\ 0,1.......0,1.......0,1\left(mol\right)\\ C_{MddBa\left(OH\right)_2}=\dfrac{0,1}{0,2}=0,5\left(M\right)\\ b,m_{\downarrow}=m_{BaCO_3}=197.0,1=19,7\left(g\right)\)
\(a,PTHH:CO_2+Ba\left(OH\right)_2\rightarrow BaCO_3\downarrow+H_2O\\ \Rightarrow n_{Ba\left(OH\right)_2}=n_{CO_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\\ \Rightarrow C_{M_{Ba\left(OH\right)_2}}=\dfrac{0,1}{0,2}=0,5M\\ b,n_{BaCO_3}=n_{CO_2}=0,1\left(mol\right)\\ \Rightarrow m_{BaCO_3}=0,1\cdot197=19,7\left(g\right)\)