# chemistry

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What mass in grams of sodium hydroxide is produced if 20.0 g of sodium metal reacts with excess water according to the chemical equation 2Na(s)+2H20(l)=2NaOH(aq)+H2(g)?

Please show me step by step how to do this because I have 5 other questions like this one on a worksheet and I have no idea how to do this stuff

• chemistry - ,

Here are the steps to go through.
1. Write the balanced chemical equation.
2. Convert what you have into mols, in this case that is convert 20 g Na to mols remembering that mols = grams/molar mass (actually atomic mass in this case).
3. Now convert mols of what you have (Na here) to mols of what you want (in this case NaOH) using the coefficients in the balanced equation. As a big hint, you use dimensional analysis to do this.
4. Now convert mols of what you want (in this case mols NaOH from step 3) to grams. grams = mols x molar mass.

Let me know if you don't understand one of the parts but work as far as you can, post your work, and tell me exactly why you don't know the next step.

• chemistry - ,