Question

HELP?? If 5.65 grams of zinc metal react with 21.6 grams of silver nitrate, how many grams of silver metal can be formed and how many grams of the excess reactant will be left over when the reaction is complete? Show all of your work.

unbalanced equation: Zn + AgNO3 Zn(NO3)2 + Ag

Answer 1

can you write the balanced equation and tell me the molecualr weight of AgNO3 and Zn(NO3)2 and atomic weight of Ag and Zn

Answer 2

Zn + 2(AgNO3) = Zn(NO3)2 + 2Ag

Answer 3

can you balance the equation?

Once you have balanced it, you need to convert grams to moles for both compounds (you know how to do that right?)

Then figure out what the limiting reagent (the reactant that is used up first, and thus dictates when the reaction is complete). To do this you simply see how many moles of product both reactants will give, the reactant that gives the least amount (smallest amount of moles) is your limiting reagent.

then simply use the moles of your limiting reagent to figure out how much product is created, and how much of the other reactant is used.

Subtract the amount of the non limiting reactant used from total amount of non limiting reagent used to figure out how much excess reactant is left over

Answer 4

Any questions?

Answer 5

Yes): I don't know how to do it at all

Answer 6

ok fine can you do this
find out molecualr weight of AgNO3 and Zn(NO3)2 and atomic weight of Ag and Zn

Answer 7

\[Moles = \frac{Grams}{MolecularMass}\]

Molecular Mass is a constant you get from your periodic table, grams are given in this question

To find molecular mass of CO2 for example

The molecular mass of Carbon = 12g/mol
The molecular mass of Oxygen = 16g/mol

12g/mol + 16g/mol + 16g/mol = 44g/mol

therefore, CO2 has a molecular mass of 44g/mol

Answer 8

can you find the moles of both reactants now?

Answer 9

If you dont follow I can give you another example

Answer 10

the unit for moles is mol btw

Answer 11

I kind of understand your example. So i do that for AgNO3?

Answer 12

Well CO2 has One Carbon atom and Two Oxygen atoms

so we add up all the individual atoms molecular weight to find the molecular weight of the compound

so,

The molecular mass of Carbon + The molecular Mass of Oxygen + the molecular Mass of oxygen = The molecular mass of CO2

Answer 13

yes you do that, then you use the formula for moles I provided (be sure to memorize it) to find the moles of each of the reactants

Answer 14

Another example,

NO

I have one nitrogen and one oxygen atom,

molecular mass of nitrogen = 14g/mol
molecular mass of oxygen = 16g/mol

14g/mol + 16g/mol = 30g/mol

therefore the molecular mass of NO is 30g/mol

if I had 30 grams of it and I wanted to convert to moles,

\[\frac{30g}{30g/mol} = 1 mol\]

therefore, I have 1 mol of NO for every 30g of NO

Answer 15

Well i understand your examples i just don't know how to do that for my problem.

Answer 16

get a periodic table and look up the molecular mass of each atom and find the total molecular mass of each compound then use the ratio I provided to find the moles

Answer 17

you need to find moles of both of your reactants, just follow the steps I did and you will be closer to solving your problem.

Answer 18

I will explain how to solve your problem using another example

Answer 19

well how to solve it once you find the moles of both reactants

Answer 20

You can post your work I dont mind checking it

Answer 21

So Zn= 65.39 ...

Answer 22

Correct, but always include units, g/mol you will lose marks and its very essential in industry

Answer 23

Now find the moles of Zn(NO3)2 you have

Answer 24

This is hopeless. Im so confused. Im sorry in waisting your time):

Answer 25

If I had the reaction:
2NO + O2 → 2 NO2

I reacted 30g of NO and 32grams of O2 and I wanted to find the amount of each reactant left over and the amount of product formed I would first convert over to moles

30g/30g/mol = 1mol of NO

32g/32g/mol = 1 mol of O2

Then I use the ratios from the balanced equation

for every 2 moles of NO I use I get 2 moles of NO2 so,

\[\frac{1mol_{NO}}{2}*2 = 1mol_{NO_2}\]

for every 1 mole of O2 I get 2 Moles of NO2 so,

\[\frac{1mol_{O_2}}{1}*2 = 2mol_{NO_2}\]

NO is the limiting reagent because it takes more moles of NO to make 1mol of NO2 than it does O2.

So we know NO is going to be used up before O2 will be in this reaction, therefore we can use it to determine the total amount of product formed and the amount of O2 left over once the reaction is complete assuming all the limiting (NO) is consumed in the reaction.

So we just apply the ratios again from our equation,

we have 1mol of NO (the 30g)

for every 2 moles of NO consumed we get 2 moles of NO

from earlier we saw that we get 1 mole of product from 1 mole of NO,

to find how much O2 was consumed in the reaction we simply back track from the product so,

\[\frac{1mol_{NO_2}}{2}*1 = 0.5mol_{O_2}\]

thus 0.5moles of O2 are consumed in the reaction,

To find the amount of left over O2 we simply use the formula

Left Over Reagent = Total Reagent utilized - Amount of Reagent Reacted

so in our case,

0.5mol O2 Left Over = 1mol O2 - 0.5mol O2 reacted

Answer 26

You can do this stuff it isn't that hard, you just need practice :) If you have any questions I'm here to help

Answer 27

You aren't wasting my time

Answer 28

Okay. sorry I'm replying a lot I'm just trying to process what your explaining to me

Answer 29

So you need to find the molecular mass of,

AgNO3

It consists of

1 Ag atom
1 N atom
3 O atoms

Find the molecular mass of Oxygen, Nitrogen and Silver then use the following formula

1*Molecular Mass Ag + 1*Molecular Mass N + 3*Molecular Mass O

Answer 30

Yeah its fine take your time, I think I was pretty detailed in my explanation so I dont really have anything more to say ha.

Answer 31

107.86Ag + 14.006N + 15.99Ox3=47.97 what do i do now?

Answer 32

Check out my example, :)

dont get confused about the example I did having 1 product and yours having 2

Answer 33

@Australopithecus go ahead very nice :)

Answer 34

you can pick either of your products to determine what the limiting reagent is

Answer 35

in your reaction

Answer 36

The molecular mass you got for AgNO3 is wrong btw but I'm sure you will see that right away

Answer 37

Yeah I'm working it out on a scratch piece of paper now. I'll let you know if i run into any more trouble. Thank you!!

Answer 38

Ok :) No problem