\(n_{H_2SO_4}=\dfrac{29,4}{98}=0,3\left(mol\right)\)
PTHH:
\(Al_2O_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2O\)
0,1 0,3 0,1
\(a,m_{Al_2O_3}=0,1.102=10,2\left(g\right)\)
\(b,C_{M\left(Al_2\left(SO_4\right)_3\right)}=\dfrac{0,1}{1,5}=\dfrac{1}{15}\left(M\right)\)