Question

Chlorine gas reacts with sold sodium to form solid sodium chloride Write a balanced chemical equation?

Answer 1

`Na(s) + 1/2Cl_2(g) rarr NaCl(s)`

Explanation:

That is the the stoichiometric equation....normally, we would give the metal a good roasting to get it volatile and able to react with the chlorine gas.. The overall reaction is exothermic...

Answer 2

`2Na_((s)) + Cl_(2(g)) -> 2NaCl_((s))`

Explanation:

• Chlorine (`Cl_(2)`) is most often seen in these types of problems as a gaseous substance (hence the little " g " on its subscript
• Sodium (`Na`) is most often seen in its solid form (as a reactant)
  in basic chem. problems like this as well (hence the little " s "
  on its subscript)
• If we combine these two we get table salt (`NaCl`) which itself is a solid substance.

Here is the general equatioon of how a Metal (`M`) will react with a nonmetal (`X`) to form an Ionic Compound (`MX`)
`color(red)(M+X->MX)`

With all that said we have...
`Na_((s)) + Cl_(2(g)) -> NaCl_((s))`

BUT...We have to balance it!

Remember moles are coefficients, if you could see them it'd look something like this...

`color(red)(1) Na_((s)) + color(red)(1) Cl_(2(g)) -> color(red)(1) NaCl_((s))`

You have 1 mole of `Na` on the left
You have 1 mole of `Cl` on the left
You have 1 mole of `NaCl` on the right

Remember atoms are subscripts, such as the `2` in `Cl_(2)`
You have 1 atom of `Na` on the left
You have 2 atoms of `Cl` on the left
You have 1 atom of `NaCl` on the right

These atoms should always be balanced with the moles on both sides. To do this we put those numbers (# of moles) in the coefficients!

So "balancing" this would give us...

`color(red)(2)Na_((s)) + color(red)(1)Cl_(2(g)) -> color(red)(2)NaCl_((s))`

If confused at all or need any more practice, this video is extremely helpful for learning how to balance basic chemical equations: