For the reaction:
Mg + 2 HCl => MgCl2 + H2
a) How many grams of HCl are required to react with 62.0 g of Mg?
All of these stoichiometry problems are about alike.
1. Write and balance the equation.
2. Convert grams Mg to moles. moles = grams/molar mass.
3. Using the coefficients in the balanced equation, convert moles Mg to moles HCl.
4. Now convert moles HCl to grams HCL. g = moles x molar mass.
To determine how many grams of HCl are required to react with 62.0 g of Mg, we need to use the molar ratio of Mg to HCl from the balanced chemical equation.
Step 1: Find the molar mass of Mg
The molar mass of Mg is 24.31 g/mol.
Step 2: Convert grams of Mg to moles of Mg
To convert grams to moles, divide the given mass by the molar mass.
moles of Mg = 62.0 g / 24.31 g/mol = 2.55 mol
Step 3: Use the molar ratio from the balanced chemical equation
From the balanced equation, we can see that the molar ratio of Mg to HCl is 1:2. This means that one mole of Mg reacts with 2 moles of HCl.
Step 4: Calculate moles of HCl
moles of HCl = 2.55 mol of Mg * (2 mol of HCl / 1 mol of Mg) = 5.10 mol
Step 5: Convert moles of HCl to grams of HCl
To convert moles to grams, multiply the moles by the molar mass of HCl.
mass of HCl = moles of HCl * molar mass of HCl
The molar mass of HCl (hydrochloric acid) is 36.46 g/mol (1 g/mol for hydrogen + 35.46 g/mol for chlorine).
mass of HCl = 5.10 mol * 36.46 g/mol = 186 grams of HCl
Therefore, 186 grams of HCl are required to react with 62.0 grams of Mg.
To determine the number of grams of HCl required to react with 62.0 g of Mg, we need to use stoichiometry and the concept of molar ratios.
Step 1: Write down the balanced chemical equation:
Mg + 2 HCl --> MgCl2 + H2
Step 2: Convert the given mass of Mg to moles:
Using the molar mass of Mg (24.31 g/mol), we can calculate the number of moles of Mg:
62.0 g Mg * (1 mol Mg / 24.31 g Mg) = 2.55 mol Mg
Step 3: Use stoichiometry and the molar ratios from the balanced equation to find the number of moles of HCl required:
From the balanced equation, the ratio between Mg and HCl is 1:2. This means that for every 1 mol of Mg, 2 moles of HCl are needed. Therefore, we can calculate the moles of HCl as follows:
2.55 mol Mg * (2 mol HCl / 1 mol Mg) = 5.10 mol HCl
Step 4: Convert moles of HCl to grams:
Using the molar mass of HCl (36.46 g/mol), we can convert moles to grams:
5.10 mol HCl * (36.46 g HCl / 1 mol HCl) = 186.4 g HCl
So, 186.4 grams of HCl are required to react with 62.0 g of Mg.