Question

Solutions of hydrogen in palladium may be formed by exposing Pd metal to H2 gas. The concentration of hydrogen in the palladium depends on the pressure of H2 gas applied, but in a more complex fashion than can be described by Henry's law. Under certain conditions, 0.84 g of hydrogen gas is dissolved in 216 g of palladium metal. (The density of the resulting solution is 11.6 g/cm2.) (a) Determine the molarity of this solution. 4.07 M (b) Determine the molality of this solution. 4.97 m (c) Determine the percent by mass of hydrogen in this solution. 4.0 %

Answer 1

Ans:- Amount of He gas 0.849 Amount of Palladium metal = 2169 density of the resulting solution = 11.69/cm3 Amount of resulting salution (0.84+216) 916.849 density (d) = mass (m) Volume (V) So Vallme of resulting solution mass of salution (9) density of solution 916-849 11.69/cm3 V - 18.693 X10-31 V= • 18.693 cm {.. cm m² = 153 L} moles of H₂ gas Amount of 12 gas Molar mass 0.849 0.42 male moles of 1₂ gas 29/mol (a) Matarity males of sodule Volume of solution (inL) 0.42 male 18.693 x 103 L

Malarity (M) = 22-4 mole/liter = 29.4M (6) Malality (m) = = males of solute mass of solvent (kg) - 103 kg 0.42 male s Igm=10 1kg = 1000gm 210 X 10 3 kg m=logy mallug = 1.94m (6) X100 % of hydrogen mass of Ha gas mass of solution X 100 = 0.387 0.849 216.849 % mass of hydrogen