Calculate the number of moles of 25g of limestone (caco3) used in a chemical reaction? (Ca=40 c=12 o=16)
2 calculate the mass of calcium chloride that can be obtained from 25g of limestone in the presence of excess hydrogen chloridw
1. mols CaCO3 = grams CaCO3/molar mass CaCO3
Answer is about 25/100 = about 0.025.
2. CaCO3 + 2HCl ==> CaCl2 + H2O + CO2
mols CaCO3 = 0.025
Using the coefficients in the balanced equation, convert mols CaCO3 to mols CaCl2. That will be 0.025 mol CaCO3 x (1 mol CaCl2/1 mol CaCO3) = 0.025 mols CaCl2 formed.
Now convert mols CaCl2 to grams. g CaCl2 = mols CaCl2 x molar mass CaCl2 = ?
Post your work if you get stuck.
Note: I have written the equation to show the use of HCl(aq) and not hydrogen chloride gas. I doubt the reaction will occur to a large extent with the gas but it will go 100% using aqueous HCl. Probably that is the point of the problem anyway; i.e., to use the aqueous HCl.
To calculate the number of moles of limestone (CaCO3) used in a chemical reaction, you need to convert the given mass of limestone into moles using the molar mass of CaCO3.
1. Determine the molar mass of CaCO3:
- The molar mass of Ca (calcium) = 40 g/mol.
- The molar mass of C (carbon) = 12 g/mol.
- The molar mass of O (oxygen) = 16 g/mol.
Calculate the molar mass of CaCO3:
Molar mass of CaCO3 = (Ca molar mass) + (C molar mass) + (3 * O molar mass)
Molar mass of CaCO3 = (40 g/mol) + (12 g/mol) + (3 * 16 g/mol)
Molar mass of CaCO3 = 100 g/mol
2. Convert the mass of limestone (25 g) into moles:
Moles of CaCO3 = (Mass of CaCO3) / (Molar mass of CaCO3)
Moles of CaCO3 = 25 g / 100 g/mol
Moles of CaCO3 = 0.25 mol
Therefore, the number of moles of 25 g of limestone (CaCO3) used in the chemical reaction is 0.25 mol.
To calculate the mass of calcium chloride (CaCl2) that can be obtained from 25 g of limestone in the presence of excess hydrogen chloride (HCl), you need to set up a balanced chemical equation and use stoichiometry.
The balanced chemical equation representing the reaction is:
CaCO3 + 2 HCl → CaCl2 + H2O + CO2
1. Determine the molar mass of CaCl2:
- The molar mass of Ca (calcium) = 40 g/mol.
- The molar mass of Cl (chlorine) = 35.5 g/mol.
Calculate the molar mass of CaCl2:
Molar mass of CaCl2 = (Ca molar mass) + (2 * Cl molar mass)
Molar mass of CaCl2 = (40 g/mol) + (2 * 35.5 g/mol)
Molar mass of CaCl2 = 111 g/mol
2. Use stoichiometry to calculate the mass of CaCl2:
From the balanced equation, we see that 1 mol of CaCO3 produces 1 mol of CaCl2.
Therefore, the mole ratio of CaCO3 to CaCl2 is 1:1.
Moles of CaCl2 = Moles of CaCO3
Mass of CaCl2 = (Moles of CaCl2) * (Molar mass of CaCl2)
Mass of CaCl2 = (0.25 mol) * (111 g/mol)
Mass of CaCl2 = 27.75 g
Therefore, the mass of calcium chloride that can be obtained from 25 g of limestone in the presence of excess hydrogen chloride is 27.75 g.