not balanced, oxygen, not equal
Explanation:
Alright, so let's go ahead and balance this equation!
The easiest way to do this is to take out a piece of paper and write down your elements on each side. Let's do it together:
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Let's count the number of molecules for each element on both sides. Starting with the left side:
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The coefficient of 2 in front of NaOH will be distributed to Na, O, and H. The subscripts for H and O only apply to themselves, so S will have only one molecule. Then our molecule counts for the reactant side (the left side) will be:
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Na: Â 2
 O:  2+4 = 6
 H:  2+2 = 4
 S:  1
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Now, let's move on to the right side:
This side only has subscripts, no coefficients, so that means that any elements that don't have subscripts (S and the second O ) will have a count of one. Knowing this, our molecule count for the product side (right side) is:
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Na: Â 2
 O:  4+1 = 5
 H:  2
 S:  1
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Let's compare our counts now:
Left side: Â Â Â Â Right side:
Na: Â 2 Â Â Â Â Â Â Na: Â 2
 O:  6        O:  5
 H:  4        H:  2
 S:  1         S:  1
We can see that our O and H molecule counts are different. So that means it's an unbalanced equation.
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Therefore, your answer will be:
The equation is not balanced because the number of hydrogen atoms and oxygen atoms is not equal in the reactants and in the products.