Final answer:
The correct name of the hydrate would be Cadmium Nitrate Pentahydrate.mass of anhydrous Cd(NO3)2 is 76.6% of its hydrate, implying that the hydrate contains about five water molecules. so dividing 94.23 g/mol by 18.015 g/mol yields roughly 5.23, which we round to approximately 5.
Step-by-step explanation:
Given that the mass of anhydrous Cd(NO3)2 is 76.6% of its hydrate mass, we can calculate the number of water molecules associated with it. Since the hydrate is 100%, the water percentage is 100% - 76.6% = 23.4%. To find the number of water molecules, we'd take the molar mass of Cd(NO3)2 (which is 308.47 g/mol) and divide it by the anhydrous compound's percentage in decimal form (which is 0.766), obtaining the hydrate molar mass of approximately 402.7 g/mol.
Subtracting the molar mass of anhydrous Cd(NO3)2, we find the mass of water in the hydrate to be approximately 94.23 g/mol. The molar mass of water is approximately 18.015 g/mol, so dividing 94.23 g/mol by 18.015 g/mol yields roughly 5.23, which we round to approximately 5. Therefore, we have Cd(NO3)2 • 5H2O, which is Cadmium Nitrate Pentahydrate. The correct answer to our question is (b) Cadmium Nitrate Pentahydrate.