Upon heating 125g MgSO4 • 7 H2O: a) how many grams of water can be obtained?
125g of MgSO4 • 7 H2O*(1 mole/ 246.47g)= moles of MgSO4 • 7 H2O
Moles of MgSO4•7H2O*(7 moles of H2O/1 mole of MgSO4•7H2O)= moles of H2O
Moles of H2O*(18.00g/mole)= mass of H2O in grams
64g
To determine the amount of water that can be obtained from heating 125g of MgSO4 • 7 H2O, we need to consider the molar ratio between water and MgSO4 • 7 H2O.
The molar mass of MgSO4 • 7 H2O can be calculated by adding the molar masses of its individual atoms:
Molar mass of MgSO4 = (1 * atomic mass of Mg) + (1 * atomic mass of S) + (4 * atomic mass of O) = (1 * 24.31 g/mol) + (1 * 32.07 g/mol) + (4 * 16.00 g/mol) = 120.37 g/mol
Molar mass of H2O = (2 * atomic mass of H) + (1 * atomic mass of O) = (2 * 1.01 g/mol) + (1 * 16.00 g/mol) = 18.02 g/mol
Therefore, the molar mass of MgSO4 • 7 H2O = (1 * molar mass of MgSO4) + (7 * molar mass of H2O) = (1 * 120.37 g/mol) + (7 * 18.02 g/mol) = 246.48 g/mol
Now, we can calculate the number of moles of MgSO4 • 7 H2O by dividing the mass (125g) by the molar mass (246.48 g/mol):
Number of moles of MgSO4 • 7 H2O = 125g / 246.48 g/mol = 0.506 moles
Since the stoichiometry of the compound shows that there are 7 moles of water for every one mole of MgSO4 • 7 H2O, we can calculate the number of moles of water:
Number of moles of water = 0.506 moles * 7 = 3.542 moles
Finally, we can multiply the number of moles of water by the molar mass of H2O to find the mass of water:
Mass of water = 3.542 moles * 18.02 g/mol = 63.87 grams
Therefore, upon heating 125g of MgSO4 • 7 H2O, 63.87 grams of water can be obtained.
To find out how many grams of water can be obtained by heating MgSO4 • 7H2O, we need to understand the chemical reaction that takes place. When hydrated magnesium sulfate (MgSO4 • 7H2O) is heated, it undergoes a process called dehydration, where water molecules are removed.
The molar mass of MgSO4 • 7H2O can be calculated by adding up the molar masses of its components:
Molar mass of MgSO4 = 24.31 g/mol (molar mass of magnesium: 24.31 g/mol + sulfur: 32.06 g/mol + 4 x oxygen: 16.00 g/mol)
Molar mass of H2O = 18.02 g/mol (molar mass of hydrogen: 1.01 g/mol + oxygen: 16.00 g/mol)
Molar mass of MgSO4 • 7H2O = (24.31 + 32.06 + 4 x 16.00) + 7 x (2 x 1.01 + 16.00) = 246.47 g/mol
Since there are 7 water molecules (H2O) per mole of MgSO4 • 7H2O, the molar mass of water is 7 x 18.02 g/mol = 126.14 g/mol.
Now we can calculate the mass of water that can be obtained by heating 125g of MgSO4 • 7H2O:
Mass of water = (mass of MgSO4 • 7H2O / molar mass of MgSO4 • 7H2O) x molar mass of water
Mass of water = (125g / 246.47 g/mol) x 126.14 g/mol
Calculating this expression will give you the answer.