Question

@surry99

Answer 1

I am here

Answer 2

hi :D

Answer 3

Okay, hold on a sec while i get a question

Answer 4

k

Answer 5

ok what do you understand about balancing equations?

Answer 6

You mind if i help?

Answer 7

Not much. All I know is that the amount of atoms of each element has to be the same.
You can help @Here_to_Help15 , just don't confuse me, hah. :)

Answer 8

Ill do my best :D

Answer 9

two principles need to be obeyed in all balanced equations:
1) Conservation of mass
2) Conservation of Charge

Answer 10

are you aware of these principles?

Answer 11

2Fe + 3Cl2 --> 2FeCl3 is your balanced equation. The coefficient for Cl2 is thus 3.

Note:
2Fe + 3Cl2 --> 2FeCl3
Left side of the equation:
2 Fe
6 Cl
Right side of the equation:
2 Fe
6 Cl, so your equation is balanced.

Answer 12

If you need a different explanation i can try an easier way?

Answer 13

i know the conservation of mass, but not charge

Answer 14

@Here_to_Help15 when you explain you really need ot break it down and explain concepts of each step. or else it means nothing to me

Answer 15

Conservation of charge is just as important and becomes very important when we deal with things lile oxidation numbers

Answer 16

things like oxidation numbers

Answer 17

Easiest way to do these is look at the half reactions:

Fe ---> Fe+3 + 3e-

Cl2 + 2e- --> 2 Cl-

Now get the same number of electrons on both sides. To do this you need to multiply the first one by 2 and the last one by 3:

2 Fe ---> 2 Fe+3 + 6 e-

3 Cl2 + 6e- ---> 6 Cl-

Add them together and you get a balanced equation:
2 Fe +3 CI2 ---> 2 FeCI3

Answer 18

oxidation numbers?

Answer 19

you do not need to know about them yet but lets go through your problem.

Answer 20

Okay

Answer 21

Fe + Cl2---> FeCl3 agreed

Answer 22

agreed

Answer 23

ok lets balance mass first...
1 Fe on left = 1 Fe on right...good
2 Cl on left but 3 Cl on right...hwat do you need to do to balance cl on both sides?

Answer 24

add another Cl

Answer 25

or...take one away

Answer 26

yes and we do that by changing the coefficients in front of the Cl2 and FeCl3..
what is the least common multiple of 2 and 3?

Answer 27

6

Answer 28

yes, so if you place a 3 in front of Cl on the left and a 2 in front of FeCl3 on the right then you will have 6 Cl on each side

Answer 29

go ahead and do that and tell me what happens to the Fe

Answer 30

Like this?
4Fe + 6Cl --> 2Fe2Cl3
..?

Answer 31

not quite
Fe + Cl2---> FeCl3
now put in the 3 in front of Cl2 and a 2 in front of FeCl3...remember we are changing the coefficients in the equation not the subscripts...
So now Ihave:
Fe + 3Cl2---> 2FeCl3 agreed

Answer 32

agreed

Answer 33

now what do we have to do to balance the Fe?

Answer 34

add one or take one away

Answer 35

Always thing in terms of adding only when you are balancing...

Answer 36

Okay

Answer 37

So how do you balance the Fe now ....remember only by adding

Answer 38

add one to the left side.

Answer 39

or in chemistry talk change the coefficient for Fe on the left from 1 to 2 go ahead

Answer 40

2Fe + 3Cl2 --> 2FeCl3

Answer 41

so far so good?

Answer 42

yep :)

Answer 43

so then the coefficent is 3, becaues that's what is in front of Cl2

Answer 44

Each species has its own coefficient:
2 For Fe
3 for Cl2
2 for FeCl3

Answer 45

I see. :) Could we try another one to make sure I get it? I have one from my chem book

Answer 46

yes but we are not quite done...
Mass is now conserved...
Lets check conservation of charge...if any of these chemical species had a real charge on them where would they appear in the symbol?

Answer 47

it would appear as a exponent. Well, nto really, but the same place

Answer 48

Exactly....do any of our species have charges?

Answer 49

no. They are all positive

Answer 50

soryr, neutral i mean

Answer 51

Yes they are all neutral so here is how we show charge is balanced...
2 mols of 0 charge from the iron + 3 mols of 0 charge form the Chlorine = 2 mols of 0 charge from the Iron(iii) chloride
this may seem trivial at this stage but trust me you will need it later

Answer 52

go ahead and post another question please

Answer 53

balance the equation
AgNO3 + H2S --> Ag2S + HNO3

That one looks complicated "/

Answer 54

:/

Answer 55

you see now your equation is balanced in mass and charge ...you are done!

Answer 56

ok, how many silvers on the left and right?

Answer 57

left: 1
right: 1

Answer 58

look at the right again

Answer 59

oh, wait. 2 (I was looking at S, not Ag)

Answer 60

ok so what do you put in front of the silver on the left?

Answer 61

2

Answer 62

go ahead and update the equation

Answer 63

2AgNO3 + H2S --> Ag2S + HNO3

but that affects the N and O, so we need to do more balancing. :)

Answer 64

2AgNO3 + H2S --> Ag2S + 2HNO3
!!! By jove, I think I got it. :)

Answer 65

yes...the NO3 is called nitrate...
how many nitrates on the left and right?

Answer 66

yes you did...now show me that charge is balanced

Answer 67

Okay...that's tougher...let's see...

Answer 68

you can do it....do any of the species have a charge?

Answer 69

I don't know what to call the AgNO3...silver nitrate?

Answer 70

they are all neutral

Answer 71

yes

Answer 72

Okay, so....
2 moles of 0 charge from the silver nitrate + 1 mole of 0 charge from the hydrogen sulfide = 1 mol of 0 charge from the silver sulfide + 2 moles of 0 charge from the hydrogen nitrate

Answer 73

(don't know if I have the right suffix there...-ide ?)

Answer 74

Excellent...hydrogen nitrate is acceptable

Answer 75

haha, "acceptable"...what else would it be called?

Answer 76

if it is dissolved in water , it is called nitric acid.

Answer 77

Want to do one more?

Answer 78

or different concept?

Answer 79

sure...um...how about this:

Reqrite the word equation as balanced chemical equation

hydrogen + sulfur --> hydrogen sullfide

Answer 80

i think that's what we just did, sort of, except backwards...the previous example had hydrogen sulfide in it...

Answer 81

go ahead...

Answer 82

H + S --> H2S
2H + S --> H2S

???

Answer 83

This is actually more complicated than it appears...
there is hydrogen the element...H
then there is hydrogen gas...H2

Answer 84

We often refer to what is called the "standard state" for a species...that means what is exists as at P = 1 atm and T = 298 K. For Hydrogen, it is H2 and for Sulfur it is S8
So the equation would be H2 + S8 ---> H2S
go ahead and balance it please

Answer 85

ah...I see.

H2 + S8 --> 8H2S
8H2 + S8 --> 8H2S

???

Answer 86

yes...the nice thing about balancing equations is you can always check them when you are done to make sure you did it correctly meaning:
1) mass must be conserved
2) charge must be conserved

Answer 87

True. Involves a lot of math

Answer 88

yes, but you love math!

Answer 89

and you will someday love chemistry too!

Answer 90

next up?

Answer 91

Haha, I'm good at math. I don't like it (well...most of the time...). xD

Answer 92

I'm going to link you to another thread

Answer 93

ok you cool with balancing now?

Answer 94

Yeah. Much better. THANK YOU! You are amazing

Answer 95

Thank you so much for doing this with me, a complete stranger. :)

Answer 96

ah...you are just a good student!