# chemistry

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for the reaction: 4NH3+5O2=4NO+6H2O; 15.0g of NH3 and 27.5g of O2 were reacted.
a). which is the limiting reactant?
b).how many moles of NO are formed from the limiting reactant in the above reaction.
i know how to do the moles but i couldn't figure out which one is the limiting reactant. to do the moles first i figured out the molecular weight for NO(30.01). but i don't understand what the mass in grams will be.

• chemistry - ,

Just think of limiting reagent problems as being two problems. Work them separately. First convert g NH3 and g O2 to mols. Then make the two problems out of it.
How many mols NO will be formed with ?? mols NH3 AND ALL THE O2 NEEDED. Get a mols NO for that.

Second problem. How many mols NO will be formed with xx mols O2 AND ALL THE NH3 NEEDED?

The SMALLER number of mols product formed will ALWAYS be the correct answer and the reactant producing that number will be the limiting reagent. There are quicker ways of doing this but this works well and it's easy to explain. You can work on quicker ways of doing it after you get the hang of it.

• chemistry - ,

oh, i think i get it. thank you.

• chemistry - ,

What is a balance chemical equation for nitric acid is a compound of acid rain that forms when gaseous nitrogen dioxide pollutant reacts with gaseous oxygen and liquid water to format aqueous nitric acid