How many moles of oxygen are formed when 58.6 g of KNO_3 decomposes according to

Question

How many moles of oxygen are formed when 58.6 g of KNO_3 decomposes according to the following reaction? The molar mass of KNO_3 is 101 g/md. 4KNO_3(s) rightarrow 2K_2O(s) + 2N_2(g) + 5O_2(g) 65 mL of 12 M HCI solution is diluted with water to a total volume of 0.15 L. What is the concentration of HCI in the final solution? According to the following balanced reaction, how many moles of HNO_3 are formed from 8.44 moles of NO_2 if there is plenty of water present? 3NO_2(g) + H_2O(l) rightarrow 2HNO_3(aq) + NO(g) If a reaction produces 0.75 moles of FeS, how many grams of FeS is produced? (Fc: 56, S: 32)

Explanation / Answer

m = 58.6 KNO3

MW = 101 g/gmol

moles = mass/MW = 58.6 g of KNO3 / 101 g/gmol = 0.58 mol of KNO3

4 moles of KNO3 will give 5 moles of O2

therefore

5/4 is the stoichiometric ration, that is

5/4*0.58 = 0.725 mol of O2 will be produced

4)

V= 65 ml

M = 12 HCl

V = 0.15 L

a) what is te new concnetration?

Apply dilution law

M1*V1 = M2*V2

M2 = M1(V1/V2) = 12M* ( 65ml / 150 ml ) = 5.2 M of HCl

M = 5.2M of HCl

5)

HNO3 are formed wehn 8.44 mol of NO2 with enough water

from the reaction

3 mol of NO2 will give you 2 mol of HNO3, therefore

stoichoimetric ratio

2/3

now apply it to the 8.44 mol

2/3*8.44 = 5.62 mol of HNO3 will be produced

6)

write the reaciton first

Fe + S ---> FeS

if there are 0.75 mol of FeS produced, then

how much grams of FeS are present?

Find MW of FeS = MW of Fe + MW of S

MW = 56+32 = 88 g/mol

mass = mol*MW = 0.75*88 = 66 g of FeS

Related Questions

Navigate

• Browse (All)
• Browse H
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.