I think 8, because you have to end up with a balanced equation.
~Hello there!
Your question: <span>Solution and hydrolysis combine to create ________ in streams.
Your answer: </span><span>Solution and hydrolysis combine to create corrosion in streams.
Hope this helps! :3
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It is the periodic table
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If you're talking about in an actual sample, you'd need more data like how many moles you have of the reactant or product.
Just in terms of the equation : there are two from the water in the reactant (left) side, and one from the sodium hydroxide and two for the hydrogen gas on the product (right) side, so 2+1+2=5 atoms of hydrogen.