Question

Calculate the mass of each product formed when 170. g of silver sulfide reacts with excess hydrochloric acid.
Ag2S(s) + HCl(aq) AgCl(s) + H2S(g) [unbalanced]

AgCl

H2S

Answer 1

@wolfe8

Answer 2

Alright first you balance the equation. Then you find the number of moles of silver that reacts.

Answer 3

i balanced it and then idk what to do after it. so its now

Ag2 S + 2H Cl ----> 2AgCl + H2 S

Answer 4

so there are 4 silver molecules right? so 4x107.9 = 431.6

Answer 5

Oh no no that's not what you do. See you are told you have 170 g of silver sulfide that reacts. THis means that before the reaction, you have 170 g of Ag2S. So find the number of mole of that.

Answer 6

so i do 170 x 6.022x 10^23?

Answer 7

Whut no. Remember number of moles is mass over molar mass? Here keep this handy: http://erhs.rcsnc.org/UserFiles/Servers/Server_4766394/Image/Donna%20Scofield/mole%20conversion%20map.bmp

Answer 8

isnt 1 mole 6.022x 10^23?

and ok so I find the mass of Ag2S? and then put that over 170?

Answer 9

6.022*10^23 is the number of PARTICLES in 1 MOLE. Number of moles is mass over molar mass. That chart should remind you of the relations with moles.

But no that's not what you do. You will do 170/(molar mass of Ag2S)

Answer 10

okk. so i understand the chart now thanks! ok so 170/247.87= 0.6858
next step?

Answer 11

Yup. So from the balanced equation, you can see that 1 mole of Ag2S gives you 2 moles of AgCl and 1 mole of H2S, right?

Answer 12

yepp

Answer 13

Anddddddd? Can you figure out what to do to get the number of moles of those products?

Answer 14

2 times .6858?

Answer 15

For AgCl yup! And for H2S?

Answer 16

i got 1.3716

it says i got it wrong

Answer 17

That is the number of moles. To convert it back to mass, what do you do? Refer to the chart or think back what we did to change mass to moles. Now do the reverse.

Answer 18

we multiply by the molar mass?

Answer 19

Yup!

Answer 20

so 1.3716 x 247.87?

Answer 21

No the molar mass of AgCl. That's the molar mass of Ag2S

Answer 22

1.3716 x 143.31 = 196.56?

Answer 23

and then for H2S dang it. i forgot the steps we took. can you please write them then step by step? our convo kinda confused me doing step by step cause of the mistakes i made.

Answer 24

1) Find the number of moles of H2S you get from the equation
2) Multiply it with molar mass of H2S

Answer 25

i got 170 which i know is wrong.

i did 170/ 34.086=4.98738
then that answer x 34.086

Answer 26

>.< Oh boy. Let's start over. We have the number of moles of Ag2S, and we know it will produce the same moles of H2S. So you multiply the number of moles of Ag2S with the molar mass of H2S

Answer 27

oiiii lol im so dumb. ok so molar mass of H2S is 34.086 and theres 1 H2S right? or was it 2?

Answer 28

Look at the balanced equation and what we said after it.

Answer 29

YA we have 1 mole of H2S

Answer 30

Yes is we start with 1 mole of Ag2S. But we started with .6858

Answer 31

okkk so .6858 x 1 x molar mass of H2S?

Answer 32

Yup

Answer 33

oko so the Ag2S is the silver sulfide that reacts and we use that mole which is the 170 / molar mass of the Ag2S and then we multiple with the moles and the mass of the substance we need correct?

Answer 34

Yup. Not technically correct term-wise but yes

Answer 35

ok thanks dude! ya i know its not correct term wise but i understand it now thanks!

Answer 36

You're welcome.

Answer 37

Calculate the mass of each product formed when 228 g of silver sulfide reacts with excess hydrochloric acid.
Ag2S(s) + HCl(aq) AgCl(s) + H2S(g) [unbalanced]



and for this one I did the steps correctly i think but I got 3546.77.....

Answer 38

2 moles for AgCl and 1 for H2S.

but idk what I did wrong now for AgCl

Answer 39

Can you make a new post for that?

Answer 40

k