How many molecules of PbCl2 are produced when 5.00 g of Pb(NO3)2 reacts with HCl?
Pb(NO3)2 + 2HCl ==> PbCl2 + 2HNO3
mols Pb(NO3)2 = grams/molar mass = ?
Then convert mols Pb(NO3)2 to mols PbCl2. That's a 1:1 conversion.
Then mols PbCl2 x (6.02E23 molecules/mol) = ?
5.00
To find the number of molecules of PbCl2 produced when 5.00 g of Pb(NO3)2 reacts with HCl, we need to follow these steps:
Step 1: Convert the mass of Pb(NO3)2 to moles.
To do this, we need to know the molar mass of Pb(NO3)2. The molar mass of Pb(NO3)2 can be calculated by summing the atomic masses of its constituent elements.
The atomic masses are:
Pb: 207.2 g/mol
N: 14.0 g/mol
O: 16.0 g/mol
The molar mass of Pb(NO3)2 is:
2 x (1 x Pb) + 2 x (1 x N + 3 x O) = 2 x (207.2) + 2 x (14.0 + 3 x 16.0) = 2 x 207.2 + 2 x 62.0 = 414.4 + 124.0 = 538.4 g/mol
Now, we can calculate the number of moles of Pb(NO3)2 using the equation:
moles = mass / molar mass
Substituting the values, we get:
moles = 5.00 g / 538.4 g/mol
moles ≈ 0.00929 mol
Step 2: Determine the stoichiometry of the balanced equation.
The balanced chemical equation for the reaction between Pb(NO3)2 and HCl is:
Pb(NO3)2 + 2 HCl -> PbCl2 + 2 HNO3
From this balanced equation, we can see that 1 mole of Pb(NO3)2 reacts to produce 1 mole of PbCl2.
Step 3: Calculate the number of moles of PbCl2 produced.
Since the stoichiometry in the balanced equation is 1:1 (1 mole of Pb(NO3)2 reacts to produce 1 mole of PbCl2), the number of moles of PbCl2 produced is equal to the number of moles of Pb(NO3)2 used.
So, the number of moles of PbCl2 produced is approximately 0.00929 mol.
Step 4: Convert moles of PbCl2 to molecules.
To determine the number of molecules of PbCl2, we need to use Avogadro's number, which is approximately 6.022 x 10^23 molecules/mol.
Number of molecules = moles x Avogadro's number
Number of molecules = 0.00929 mol x 6.022 x 10^23 molecules/mol
Number of molecules ≈ 5.59 x 10^21 molecules
Therefore, approximately 5.59 x 10^21 molecules of PbCl2 are produced.