Anonymous
Anonymous asked in Science & MathematicsChemistry · 6 years ago

# How do you Balance equations? (Chemistry)?

Okay so I know how to do problems like __H2 + __Cl2 --> __HCl

it would be _1_H2+_1_Cl2 --> _2_HCl

because h = 2 and Cl = 2 so you multiply H by 2 and Cl by 2

soooo they are equal right? I get those questions but

how do I do questions like this?

__Na + __Cl2 --> __NaCl

or

__K + __MgBr2 --> __KBr + __Mg

this is not my homework, I was absent from class so I need to catch up, thanks for help.

Relevance
• Lexi R
Lv 7
6 years ago

__Na + __Cl2 --> __NaCl

The Na is already balanced, so look at the Cl, you have 2 Cl on the LHS and only 1 Cl on the right hand side. Put a 2 in front of NaCl. (remember, you can only put numbers in front of compounds to balance an equation)

__Na + __Cl2 --> _2_NaCl

but, this throws out the Na. Now we need to re-balance it by putting a 2 in front of Na on the LHS

_2_Na + __Cl2 --> _2_NaCl

balanced

__K + __MgBr2 --> __KBr + __Mg

K and Mg are balanced initially, but Br is not, put a 2 in front of the KBr to balance the Br

__K + __MgBr2 --> _2_KBr + __Mg

but now K is unbalanced, put a 2 in front of the K

_2_K + __MgBr2 --> _2_KBr + __Mg

balanced

Also, handy tip..... as a general rule leave Hydrogen (H2) and Oxygen (O2) and water (H2O until last in equations that have these molecules. Do all the other atoms first.