How many grams of kclo3 are needed to produce of 4.26 moles of o2? 2 kclo3 2 kcl + 3 o2 a. 348 g b. 136 g c. 174 g d. 522 g e. 783 g

The answer is c. 173 g

Explanation:

You know the reaction :

KClO3 ⇒ 2 KCl + 3 O2

By stoichiometry, that is, the amount of reagents and products in a chemical reaction when it is balanced (as in this case), it is known that for 2 moles of O2, 1 mole of KCLO3 is needed. So you can do the following rule of three to know the number of moles to produce 4.26 moles of 02:

If 1 mole of KClO3 is necessary to produce 3 moles of O2, how many moles are needed to produce 4.26 moles of 02?

So you need 1.42 moles of KClO3

Now it is necessary to know the molar mass of KClO3, which is the mass that contains 1 mole of the substance. For that you need to know the mass of K, Cl and O:

So, the molar mass of KClO3 is:

39 g/mol + 35.45 g/mol + 3*16 g/mol=122.45 g/mol

because it contains 1 atom of K, 1 atom of Cl and 3 atoms of O.

Now, to calculate the mass representing 1.42 moles of KClO3 (needed to produce 4.26 moles of O2) you simply multiply that amount of moles by the molar mass:

This means that approximately 174 g of KClO3 are necessary to produce 4.26 moles of O2.

if you're asking what comes out, it's steam.