Lab6: Stoichiometry Lab worksheet
Name: ______________________
Total Points:15. Complete the following worksheet. Show your calculations.
1. Consider the following equation.
KClO3(s) → KCl (s) + O2(g)
a. Balance the above equation.
b. In a reaction 1.20 g of oxygen was produced. Determine the number of moles
of oxygen.
c. Write the mol ratio between KClO3 and oxygen.
d. Determine the number of moles of KClO3 reacted.
e. Determine the mass of KClO3 reacted.
2. Consider the following equation:
KHCO3(aq) + HCl(aq) → KCl + CO2 (g) + H2O(l)
A reaction was carried out using excess HCl and 2.00 g of KHCO3.
a. Calculate the moles of KHCO3.
b. What is the mol ratio between KCl and KHCO3?
c. Calculate the moles of KCl that will form.
d. Calculate the mass of KCl that will form. (Theoretical yield)
e. After the experiment, 1.10 g of KCl was actually recovered. Calculate the
percent yield.
f. If 2.00 g of KHCO3 is reacted with 0.0050 mols of HCl, which one is limiting
reactant? Show your calculation.
3. Consider the following equation:
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
An experiment was carried out using 0.850 g of Mg in excess HCl.
a. Calculate the moles of Mg.
b. Calculate the mass of H2 produced.
c. Calculate moles of HCl that will react with 0.850 g Mg.
d. Calculate the number of Mg atoms in 0.850 g sample.
Useful equations:
1 mol = 6.022*1023 particles
Mass = no. of mols * molar mass
No. of moles =
𝑚𝑎𝑠𝑠
𝑚𝑜𝑙𝑎𝑟 𝑚𝑎𝑠𝑠
Percent yield =
𝑎𝑐𝑡𝑢𝑎𝑙 𝑦𝑖𝑒𝑙𝑑
𝑡ℎ𝑒𝑜𝑟𝑒𝑡𝑖𝑐𝑎𝑙 𝑦𝑖𝑒𝑙𝑑
x 100%