Posted by Josh on Saturday, March 17, 2007 at 10:58pm.
How many grams of hydrochloric acid are required to react completely with 4.30g of zinc?
How many molecules of gas will be produced?
For Further Reading
science - DrBob222, Saturday, March 17, 2007 at 11:07pm
1. Write the balanced chemical equation.
Zn + 2HCl ==> ZnCl2 + H2
2. Convert grams Zn to mols.
mols = grams/atomic mass Zn.
3. Using the balanced equation, convert mols Zn to mols HCl.
4. Now convert mols HCl to grams HCl.
grams HCl = mols HCl x molar mass HCl.
Post your work if you get stuck.
science - Josh, Saturday, March 17, 2007 at 11:19pm
Zn=1 Zn=1
H=2 H=2
Cl=2 Cl=2
mols= 4.30/65.4
=.065749235
I don't know what to do next
science - Josh, Saturday, March 17, 2007 at 11:25pm
mol of HCl=73?
science - DrBob222, Sunday, March 18, 2007 at 12:55am
1. Write the balanced chemical equation.
Zn + 2HCl ==> ZnCl2 + H2
2. Convert grams Zn to mols.
mols = grams/atomic mass Zn.
You have 4.30/65.4 = 0.0658 mols Zn which is correct.
3. Using the balanced equation, convert mols Zn to mols HCl.
Use the coefficients in the balanced equation to convert mols Zn to mols HCl.
mols HCl = 0.0658 mols Zn x (2 mols HCl/1 mol Zn) =?? mols HCl
4. Now convert mols HCl to grams HCl.
grams HCl = mols HCl x molar mass HCl.
??mols HCl from step 3 x molar mass HCl = xx
post your work if you have trouble.
science - Jennifer, Sunday, March 18, 2007 at 1:08am
4.74
science - Josh, Sunday, March 18, 2007 at 2:00am
what is the answer for questions a and b? or have we gotten there yet?
This is crazy reposting all the work, which is repetitive.
You write the balanced equation, which you have. You determine the moles of zinc, which you have. You determine the moles of HCl it takes to react with the moles of zinc (look at the balanced equation for the ratio). Finally, convert those moles of HCL to grams of HCl.
For the molecules of gas, use the balanced equation to give you the ratio of moles H2 per mole of zinc. Then, from the ratio, and the moles of zinc, you can calculate the moles of H2. Molecules? moles of H2 times avagradros number.
see...http://members.aol.com/rtccpu/DOCs/stoich/DoubleYDiagram.PDF
1.204?
To find the number of grams of hydrochloric acid required to react completely with 4.30g of zinc, we can follow these steps:
1. Write the balanced chemical equation:
Zn + 2HCl → ZnCl2 + H2
2. Convert grams of zinc to moles:
Moles = grams/atomic mass Zn
Moles = 4.30g/65.4g/mol = 0.0658 mol Zn
3. Use the balanced equation to convert moles of Zn to moles of HCl:
From the equation, we see that 1 mole of Zn reacts with 2 moles of HCl.
Moles of HCl = 0.0658 mol Zn * (2 mol HCl/1 mol Zn) = 0.1316 mol HCl
4. Convert moles of HCl to grams of HCl:
Grams HCl = Moles HCl * Molar mass HCl
Molar mass of HCl:
Atomic mass of H = 1g/mol
Atomic mass of Cl = 35.4g/mol
Molar mass HCl = 1g/mol + 35.4g/mol = 36.4g/mol
Grams HCl = 0.1316 mol HCl * 36.4g/mol = 4.79g HCl
Therefore, 4.79 grams of hydrochloric acid are required to react completely with 4.30g of zinc.
To calculate the number of molecules of gas produced, we continue with these steps:
5. Use the balanced equation to find the ratio of moles of H2 gas to moles of Zn:
From the balanced equation, we see that 1 mole of Zn produces 1 mole of H2 gas.
6. Calculate the moles of H2 gas:
Moles of H2 = 0.0658 mol Zn
7. Convert moles of H2 gas to molecules of H2 gas:
One mole of any gas contains Avogadro's number of molecules, which is approximately 6.022 x 10^23.
Molecules of H2 = Moles of H2 * Avogadro's number
Molecules of H2 = 0.0658 mol H2 * 6.022 x 10^23 molecules/mol = 3.96 x 10^22 molecules
Therefore, approximately 3.96 x 10^22 molecules of H2 gas will be produced.