Sodium (Na) reacts with chlorine gas (Cl2

) to form sodium chloride (NaCl) as shown in the

equation:

2Na + Cl2 → 2NaCl

If 4 moles of chlorine gas react, how many moles of sodium will react?

Remark

The balance numbers in front of the chemicals tell you how to set up the proportion to solve your question

For every 2 moles Na only 1 mole of Cl2 is required.

Equation

2 moles Na:1 mole Cl2 : : x moles Na:4 moles Cl2

Solution

2/1 = x/4 Cross multiply

2*4 = x*1

8 = x

Conclusion

8 moles of Na will be used. <<< Answer

The equation shows that for every mole of Cl2 that react, 2 moles of Na react too. You can find how many moles of sodium react like this:

4 moles Cl2 x (2 moles Na / 1 mole Cl2) = 8 moles Na

8 moles of Sodium react