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# I am not sure if this Empirical Formula for Lithium Carbonate is right watch

1. Okay basically I have done this:

% mass for Lithium is 18.9, Carbon is 16.2 and Oxygen is 64.9.

then I did- % mass / Ar (relative atomic mass)

Lithium- 18.9 / 7 (not sure if it would be 14 because there are 2 Lithiums in Lithium Carbonate) that equaled 2.70 mole ratio.

Carbon- 16.2 / 12 = 1.35

Oxygen- 64.9 / 16 = 4.10

is this right? If not can you please show me how to get the correct answer thank-you .

This is my first time doing this equation.
2. (Original post by Tidalwave)
Okay basically I have done this:

% mass for Lithium is 18.9, Carbon is 16.2 and Oxygen is 64.9.

then I did- % mass / Ar (relative atomic mass)

Lithium- 18.9 / 7 (not sure if it would be 14 because there are 2 Lithiums in Lithium Carbonate) that equaled 2.70 mole ratio.

Carbon- 16.2 / 12 = 1.35

Oxygen- 64.9 / 16 = 4.10

is this right? If not can you please show me how to get the correct answer thank-you .

This is my first time doing this equation.
The empirical formula is the simplest possible ratio of particles in the compound ...

lithium carbonate is Li2CO3 ... this IS the simplest ratio!
3. [QUOTE=charco;42117394]The empirical formula is the simplest possible ratio of particles in the compound ...

lithium carbonate is Li2CO3... this IS the simplest ratio.

I knew the chemical formula for Lithium Carbonate. So basically I am trying to find out the mole ratio. I am confused :/
4. Yes, It's correct.

5. Yes, It's correct.

So does this formula tell me the mole ratio? but how come for Oxygen the mole is 4.10 but the Lithium Carbonate has three oxygens? I am confused.
6. (Original post by Tidalwave)
Yes, It's correct.

So does this formula tell me the mole ratio? but how come for Oxygen the mole is 4.10 but the Lithium Carbonate has three oxygens? I am confused.
It is simply a mathematical expression of the ratio.
To express a ratio in its simplest form, divide through by the smallest value (that isn't 1)
e.g.
1.7 : 3.4 : 5.1
1 : 2 : 3
As its chemistry, you ought to have an integer number of moles
7. (Original post by Tidalwave)
Okay basically I have done this:

% mass for Lithium is 18.9, Carbon is 16.2 and Oxygen is 64.9.

then I did- % mass / Ar (relative atomic mass)

Lithium- 18.9 / 7 (not sure if it would be 14 because there are 2 Lithiums in Lithium Carbonate) that equaled 2.70 mole ratio.

Carbon- 16.2 / 12 = 1.35

Oxygen- 64.9 / 16 = 4.10

is this right? If not can you please show me how to get the correct answer thank-you .

This is my first time doing this equation.
(Original post by Tidalwave)
Yes, It's correct.

So does this formula tell me the mole ratio? but how come for Oxygen the mole is 4.10 but the Lithium Carbonate has three oxygens? I am confused.
Lithium- 18.9 / 7 = 2.70

Carbon- 16.2 / 12 = 1.35

Oxygen- 64.9 / 16 = 4.10

Divide them all by the smallest to get the ratio so divide them all by 1.35

Li becomes 2, C becomes 1 and Oxygen becomes 3.
8. Lithium- 18.9 / 7 = 2.70

Carbon- 16.2 / 12 = 1.35

Oxygen- 64.9 / 16 = 4.10

Divide them all by the smallest to get the ratio so divide them all by 1.35

Li becomes 2, C becomes 1 and Oxygen becomes 3.

Ohhhhh I now understand, thanks! I didn't realise you had to divide it by the smallest ratio.

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