2Al + 3H2SO4 → Al2(SO4)3 + 3H2
Mole of Al taken = \(\frac{5.4 }{ 27}\) = 0.2
Mole of H2SO4 taken = \(\frac{{50 \times 5}}{{1000}} = 0.25\)
As \(\frac{0.2}{2} > \frac{0.25}{3}, \text{H}_2\text{SO}_4\) is limiting reagent
Now, moles of H2 formed = \(\frac{3}{3} \times 0.25 = 0.25\)
Therefore Volume =\(0.25 \times 0.082 \times \frac{300}{1} = \frac{24.6}{4} = 6.15 \, \text{L}\)
Let $ a_0, a_1, ..., a_{23} $ be real numbers such that $$ \left(1 + \frac{2}{5}x \right)^{23} = \sum_{i=0}^{23} a_i x^i $$ for every real number $ x $. Let $ a_r $ be the largest among the numbers $ a_j $ for $ 0 \leq j \leq 23 $. Then the value of $ r $ is ________.
A temperature difference can generate e.m.f. in some materials. Let $ S $ be the e.m.f. produced per unit temperature difference between the ends of a wire, $ \sigma $ the electrical conductivity and $ \kappa $ the thermal conductivity of the material of the wire. Taking $ M, L, T, I $ and $ K $ as dimensions of mass, length, time, current and temperature, respectively, the dimensional formula of the quantity $ Z = \frac{S^2 \sigma}{\kappa} $ is: