in a chemical reaction, 5.2 grams of magnesium reacts with hydrogen nitrate. Calculate the amount of magnesium nitrate that is produced and the amount of hydrogen nitrate needed to react with the magnesium.
Mg + 2HNO3 ==> Mg(NO3)2 + H2
mols Mg = grams/molar mass
mols Mg(NO3)2 = mols Mg (look at the mole ratio) which is 1 mol Mg to 1 mol Mg(NO3)2.
Then grams Mg(NO3)2 = mols x molar mass.
For HNO3 needed,
convert mols Mg to mols HNO3 and convert mol HNO3 to grams as in the above.
To calculate the amount of magnesium nitrate produced and the amount of hydrogen nitrate needed, we need to use the concept of stoichiometry.
1. Write the balanced chemical equation for the reaction:
Mg + 2HNO3 → Mg(NO3)2 + H2
2. Determine the molar mass of magnesium (Mg), which is 24.31 g/mol.
3. Convert the given mass of magnesium (5.2 grams) to moles:
Moles of Mg = Mass of Mg / Molar mass of Mg
= 5.2 g / 24.31 g/mol
≈ 0.214 moles
4. From the balanced equation, we can see that the stoichiometric ratio between magnesium (Mg) and magnesium nitrate (Mg(NO3)2) is 1:1. Therefore, the moles of magnesium nitrate produced will be equal to the moles of magnesium.
Moles of Mg(NO3)2 = Moles of Mg
= 0.214 moles
5. Now, let's find the molar mass of hydrogen nitrate (HNO3), which includes hydrogen (H), nitrogen (N), and oxygen (O). Using the periodic table, we find the molar masses:
H = 1.01 g/mol
N = 14.01 g/mol
O = 16.00 g/mol
Molar mass of HNO3 = (1 × H) + (1 × N) + (3 × O)
= 1.01 g/mol + 14.01 g/mol + 3 × 16.00 g/mol
= 63.02 g/mol
6. Since the stoichiometric ratio between magnesium (Mg) and hydrogen nitrate (HNO3) is 1:2, we need to calculate the moles of HNO3 required.
Moles of HNO3 = 2 × Moles of Mg
= 2 × 0.214 moles
= 0.428 moles
7. Finally, calculate the mass of hydrogen nitrate needed by multiplying the moles by the molar mass:
Mass of HNO3 = Moles of HNO3 × Molar mass of HNO3
= 0.428 moles × 63.02 g/mol
≈ 27.02 grams
Therefore, the amount of magnesium nitrate produced is approximately 0.214 moles, and the amount of hydrogen nitrate needed to react with the magnesium is approximately 27.02 grams.