## anonymous 3 years ago #1: The theoretical yield of a reaction is 5.00 moles of potassium permanganate (KMnO4). If the reaction actually produces 695.2 g KMnO4, what is the percent yield of the reaction? A. 78% B. 83% C. 88% D. 120% **idk :( which is it? @UnkleRhaukus :)

1. anonymous

#2: The equation for the formation of water from hydrogen gas and oxygen gas is 2H2 + O2 2H2O. How many grams of water can be made from 160 g of oxygen gas? A. 160 g B. 180 g C. 320 g D,. 405 g **idk this one either :/

2. anonymous

idk :(

3. anonymous

is it 4?? or is it 3? ;/

4. anonymous

idk how to do that :/ can u pls show me? and this if for #1 right>?

5. anonymous

#3: Consider the hydrazinenitrogen tetroxide rocket fuel reaction: 2N2H4 + N2O4 3N2 + 4H2O How many grams of N2H4 will be consumed by 92 g of N2O4? A. 128 g B. 64 g C. 32 g D. 16 g **my answer; C. 32 g is that right?? not too sure =/

6. anonymous

#4: Consider this reaction: N2 + 3H2 2NH3 Suppose you have 2.0 L of nitrogen. How many liters of hydrogen do you need for a complete reaction? (One mole of any gas occupies 22.4 L under certain conditions of temperature and pressure. Assume those conditions for this question.) A. 2.6 L B. 6.0 L C. 9.0 L D. 10.0 L **my answer: A. 2.6 L is that right?? again, not too sure :/

7. UnkleRhaukus

8. anonymous

#5: A reaction produces 10.5 L of oxygen, but was supposed to produce 1 mol of oxygen. What is the percent yield? (One mole of any gas occupies 22.4 L under certain conditions of temperature and pressure. Assume those conditions for this question.) A. 22% B. 47% C. 67% D. 94% **my answer; B. 47% is that right?

9. anonymous

oh oaky sorry!! btw, that's all the questions so ill just leave em there and we can scroll up! is that oaky? and oaky i seee... what do i do next?

10. UnkleRhaukus

ok,

11. anonymous

so what do i do now? and is this #1 right?

12. UnkleRhaukus

#1: how many moles is $$695.2 [\text g] \text{KMnO}_4$$ ? first you need to work out the molar mass of $$\text{KMnO}_4$$ $M_{\text{KMnO}_4}=M_{\text K}+M_{\text{Mn}}+4M_{\text O}=$

13. UnkleRhaukus

$M_{\text K}=39 \quad\text g /\text{mol}$$M_{\text {Mn}}=55 \quad\text g /\text{mol}$$M_{\text {O}}=16 \quad\text g /\text{mol}$

14. anonymous

okay so what's after that? how do i see what percentage it is?

15. UnkleRhaukus

have you worked out the molar mass of KMnO4?

16. anonymous

noo ;( idk how to do that :(

17. UnkleRhaukus

$M_{\text{KMnO}_4}=M_{\text K}+M_{\text{Mn}}+4M_{\text O}=$

18. anonymous

ohh but idk what to do there :/ at least not on this one :(

19. UnkleRhaukus

maybe it is best to try these when you aren't so tired

20. anonymous

oaky :) i will!! thank youuu :D