In the effect of very unfortunate accident (details of which you don't want to reveal to your parents) car battery containing 500 g of sulfuric acid was dropped into your baby-brother plastic pool standing in the backyard. You have 750 g sack of sodium bicarbonate that you want to use to neutralize pool content before emptying it. Will it be enough or not?

Such things happen but let's be serious about, as sulfuric acid from battery is a really dangerous stuff. Reaction of neutralization is

H2SO4 + 2NaHCO3 → Na2SO4 + 2H2O + 2CO2

As we are asked only about whether known amount of reactant will be enough or not, we can do calculations once, for any reactant - and once we will know stoichiometric mass of the second reactant needed answer will be obvious. Let's try for sulfuric acid:

98.08 g:168.0 g
500 g:x g

Note that 168 g is twice a molar mass of sodium bicarbonate (or, more properly, sodium hydrogen carbonate), as every mol of sulfuric acid reacts with two moles of said reagent.

Our proportion is

98.08 g : 168 g = 500 g : x g

and x = 500 g / 98.08 g × 168 g = 850.2 g

Obviously we are short about 100 g of bicarbonate, so you better go and look for some more (or for some other salt to neutralize solution, like calcium carbonate).

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