Assuming an efficiency of 30.80%, calculate the actual yield of magnesium nitrate formed from 147.4 g of magnesium and excess copper(II) nitrate.
Mg+Cu(NO3)2=Mg(NO3)2+Cu
is anyone able to solve this? ive gotten the answer wrong twice
Mg + Cu(NO3)2 ==>Mg(NO3)2 + Cu
mols Mg = 147.4/atomic mass Mg = ?
mols Cu(NO3)2 formed = mols Mg from above since it is 1 mol Mg = 1 mol Cu(NO3)2.
g Cu(NO3)2 = mol Cu(NO3)2 x molar mass Cu(NO3)2 = ?
That is the theoretical yield if it were 100%.
Take that number and multiply by 0.3080 = ?
Piece o' cake.
To calculate the actual yield of magnesium nitrate, you need to follow these steps:
Step 1: Write and balance the chemical equation.
The balanced chemical equation for the reaction between magnesium and copper(II) nitrate is:
Mg + Cu(NO3)2 → Mg(NO3)2 + Cu
Step 2: Calculate the molar mass of the relevant substances.
- The molar mass of magnesium (Mg) is 24.305 g/mol.
- The molar mass of copper(II) nitrate (Cu(NO3)2) can be calculated as follows:
Copper (Cu) has a molar mass of 63.546 g/mol.
Nitrogen (N) has a molar mass of 14.007 g/mol.
Oxygen (O) has a molar mass of 16.00 g/mol.
Since there are two nitrate ions (NO3) in the formula, we multiply the molar mass of one nitrate ion by 2.
Molar mass of Cu(NO3)2 = (63.546 g/mol) + 2 * [(14.007 g/mol) + (3 * 16.00 g/mol)].
Step 3: Calculate the number of moles of magnesium.
To find the number of moles of magnesium, use the formula:
Number of moles = Mass / Molar mass.
Number of moles of Mg = 147.4 g / 24.305 g/mol.
Step 4: Determine the limiting reagent.
To determine the limiting reagent, compare the moles of magnesium to the moles needed based on the balanced equation. The balanced equation tells us that the stoichiometric ratio between Mg and Cu(NO3)2 is 1:1. So, if the number of moles of magnesium is larger, then it is in excess.
Step 5: Calculate the theoretical yield.
Theoretical yield is the maximum amount of product obtained assuming complete conversion. In this case, the theoretical yield of magnesium nitrate (Mg(NO3)2) is equal to the same number of moles as magnesium (since the stoichiometric ratio between them is 1:1). You can calculate the theoretical yield by multiplying the number of moles of magnesium by the molar mass of magnesium nitrate (Mg(NO3)2).
Step 6: Calculate the actual yield.
The actual yield is given as a percentage of the theoretical yield. In this case, the given efficiency is 30.80%. You can calculate the actual yield by multiplying the theoretical yield by the efficiency percentage.
Finally, plug in the values and perform the calculations to obtain the actual yield of magnesium nitrate formed from the given amount of magnesium and excess copper(II) nitrate.