Question

1.)Convert: 2.6g to 6.73g F

2.)7.61 g of potassium(K) reacted with 14.6g of chlorine(Cl) to form the compound Kcl. What mass % of the compound is due to Potassium?

Answer 1

1) 2.6 g WHAT to 6.73 g F? What's the question?

2)This is a limiting reagent problem.
Step 1 is to write and balance the equation.

Convert 7.61 g K to moles. moles = grams/molar mass.
Convert 14.6 g Cl2 to moles the same way.

Convert moles K to moles KCl.
Convert moles Cl2 to moles KCl.
It is likely that the number of moles KCl will be different and one of the values must be wrong. The correct value in limiting reagent problems is ALWAYS the smaller value.

Now convert the moles KCl to grams. g = moles x molar mass.
Post your work if you get stuck.