Question

How many grams of magnesium oxide can be produced when 97.2 g Mg react with 88.5 g O2?

Unbalanced equation: Mg + O2 → MgO

Answer 1

First balance the equation :)

Answer 2

I dont know how...

Answer 3

Mg + O2 → MgO

Well you see that there are 2 oxygens on the reactant side while there is only 1 oxygen on the product side. To balance the oxygen, you can multiply the MgO on the product side by 2. So you have

Mg + O2 → 2MgO

Now if you take a look at the Magnesiums, there are 2 on the product, but only 1 on the reactant. You can multiply the magnesium on the reactant side by 2 to get both sides to equal with respect to magnesium.

2Mg + O2 → 2MgO

Are there equal amounts of each atom on both sides? Yes! That is the final balanced equation.

Answer 4

So 2Mg + O2 ---> 2MgO is the balanced equation?

Answer 5

Mhm, do you know where to go next?

Answer 6

Not really I am kind of lost, this is yesterdays busywork for chem and I had the flu therefor I was not there

Answer 7

Oh, okay. Can you tell me what you interpret from the balanced equation?

Answer 8

2Magnesium + Oxygen 2 ----> 2MagnesiumOxygen

Answer 9

Hello? Look I really would just appriciate it explained to me in detail I have to go to bed soon and I am kind of in a time crunch here

Answer 10

Yes, but what does it say about the actual reaction that takes place?

When 2 moles of magnesium reacts with 1 mole of oxygen gas, 2 moles of magnesium oxide will be formed.

So let's say you mix 10 moles of Mg with 5 moles, you'll get 10 moles of MgO2.

You can solve your problem by converting the masses given to moles and using this ratio.

Answer 11

Sorry for the late replies, my printer got in a jam and I'm a bit busy atm.

Answer 12

Ok well I am confused

Answer 13

How many moles of Mg are in 97.2 g of Mg?
How many moles of O2 are in 88.5 g of O2?

Answer 14

@dumbcow please help!

Answer 15

I see how it is! It's okay... ;)

Answer 16

I just am not understanding you! I am sorry!

Answer 17

@ganeshie8 please help!

Answer 18

@AccessDenied please help!

Answer 19

@Outkast3r09 please help!! ANYBODY!

Answer 20

@surdawi please help!

Answer 21

@Rogue I NEED HELP!

Answer 22

-_- sigh...

Answer 23

?

Answer 24

How many grams of calcium phosphate can be produced when 89.3 grams of calcium chloride reacts with excess sodium phosphate?

Unbalanced equation: CaCl2 + Na3PO4 → NaCl + Ca3(PO4)2

Show, or explain, all of your work along with the final answer.

balanced equation
3 CaCl2 + 2 Na3PO4 = 6 NaCl + Ca3(PO4)2

moles CaCl2 = 89.3 g /110.984 g/mol=0.805
moles Ca3(PO4)2 = 0.805/3 =0.268
mass Ca3(PO4)2 = 0.268 mol x 310.17 g/mol=83.1 g

is this at least right

Answer 25

I am going to cry

Answer 26

How many grams of magnesium oxide can be produced when 97.2 g Mg react with 88.5 g O2?

2Mg + O2 --> 2MgO

The atomic mass of magnesium is ~24.31 grams/mole (1 mole of magnesium weighs 24.31 grams). So in 97.2 grams of magnesium, there is 97.2/24.31 = 4 moles of magnesium. Looking at the reaction, 2 moles of magnesium yields 2 moles of magnesium oxide. So 4 moles of magnesium should yield 4 moles of magnesium oxide.

You also have to consider the amount of oxygen you have. 1 mole of O2 weighs ~32 grams and so in 88.5 grams of oxygen, there are 88.5/32 = 2.77 moles. From the reaction, 1 mole of O2 yields 2 moles of MgO. So 2.77 moles of O2 should yield 5.54 moles of MgO.

However, both the Mg and the O2 are reacting and there is only a limited amount of each. The Mg will run out before the oxygen and so only 4 moles of magnesium oxide can be produced.

1 mole of MgO weighs ~ 40.3 grams. So 4 moles of MgO, your final product, should weigh ~ 161.2 grams.

Answer 27

Does that make sense?

Answer 28

Yeah, you have the calcium phosphate problem right! :) It's actually a bit easier. Good job though :D

Answer 29

Our equation is 2Mg + O2=2MgO also 4Mg + 2O2=4MgO
2*(24.3+16)
4*(24.3+16)
161.2 gram of MgO formed
Is this right

Answer 30

@Rogue ?

Answer 31

Yeah, that's correct.

Answer 32

Thank you!!

Answer 33

@Rogue are you sure?

Answer 34

Fairly certain :)

Answer 35

@Rogue is this right as well?
What is the limiting reactant when 8.4 moles of lithium react with 4.6 moles of oxygen gas?
Unbalanced equation: Li + O2 → Li2O
4Li + O2 --> 2Li2O
8.4(2/2) = 8.4
4.6 O2(2/1 O2) = 9.2 g

Answer 36

4 moles of lithium and 1 mole of O2 would yield 2 moles of Li2O.

8.4 moles of lithium and x moles of O2 would yield 4.2 (8.4/2) moles of Li2O.
x = 8.4/4 = 2.1 moles of O2 required to react with all the Lithium. We have 4.6 moles of O2, more than enough.

x moles of lithium and 4.6 moles of O2 would yield 9.2 (4.6*2) moles of Li2O.
x = 4*4.6 = 18.4 moles of lithium is required to completely exhaust the 4.6 moles of O2. We only have 8.4 moles of Lithium, so there isn't enough Li.

Lithium is the limiting reactant.

Answer 37

No.. This is not a practice exam. This is a module quiz from FLVS so using this answer will be an academic integrity violation. Plus it has a obvious mistake in it.

Mr. Carlyle
FLVS Chemistry Instructor

This question is a violation of the OpenStudy Guidelines. The question is from an online school plus a violation by solicitation for members to unknowingly assist them cheating on an exam. 30653065chem30653065