How many mol MgNO32 are produced from 2.5 mol KNO3?

Answer 1

First you have to get to a balanced equation

2KNO3+1Mg=1Mg(NO3)2+2K

Then you do a mole to mole equation

2.5molKNO3x1mol Mg(NO3)2/(over)2molKNO3=1.25mol Mg(NO3)2

So your answer is 1.25mol Mg(NO3)2

But if you follow the rules of signicicant figures you need to have as many digits in your answer as the given. 2.5mol has 2 significant figures(digits) so your answer needs to have 2 digits

Rounding to two digits we get 1.3molMg(NO3)2

Your answer is 1.3molMg(NO3)2

Answer 2

You would need to write the balanced reaction between KNO3 and Mg(NO3)2, and then use the stoichiometry of the two compounds in the reaction to determine the mole ratio between them. From this, you can calculate how many moles of Mg(NO3)2 can be produced from 2.5 moles of KNO3.