Answer:
825 g
Step-by-step explanation:
Here's my work:
500g Cl2 l  1mol Cl2  l  2 mol NaCl  l  58.5 g NaCl
        l  71 g Cl2   l  1 mol Cl2    l   1 mol NaCl Â
= 823.94 Â - the rounding can be a little off
The first thing you have to do is convert the 500 g of Cl2 into moles.  So you get the mass of Cl which is 35.5, but Cl is diatomic by itself so you multiply 35.5 x 2 and get 71.  now on the third column you are comparing the mol ratios of the equation.  The equation is 2Na + Cl2 ---> 2NaCl, so you see that there is no coefficient in front of Cl2 so that means there is 1 mol, and then you see that in the product there is a  coefficient of 2 in front of NaCl so that means there is 2 moles.  Then finally you have to convert the moles backs into grams where you just add the masses of Na and Cl .  You multiply across the top  and then divide that number by the bottom row.
