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### Denoting brackets/parentheses

Posted: Sun Jan 13, 2019 9:12 am
Can someone please clarify when we use brackets vs. parentheses to denote materials in the gas law?

### Re: Denoting brackets/parentheses

Posted: Sun Jan 13, 2019 9:51 am
I think brackets are usually used to denote concentration, such as [J] is the concentration of solution/gas J, whereas parentheses are used to show that you are multiplying values. In the ideal gas law, Dr. Lavelle used brackets when rewriting the formula as P = [conc.]RT, but for calculations it shouldn't matter.

### Re: Denoting brackets/parentheses

Posted: Sun Jan 13, 2019 9:54 am
I'm pretty sure brackets indicate concentration so for Kc [H20] indicates the concentration of water, but with Kp you have (PCl2). You don't need brackets to indicate concentration for this because the P indicates the pressure of the gas. I hope this helps!

### Re: Denoting brackets/parentheses

Posted: Sun Jan 13, 2019 1:32 pm
My T.A. said that brackets indicate concentrations while parentheses are for calculating the K of partial pressure. It would be incorrect to do [Pco2] for example because you'd be trying to calculate the concentration of a partial pressure, which isn't correct.

### Re: Denoting brackets/parentheses

Posted: Sun Jan 13, 2019 2:37 pm
Brackets are for concentration and parentheses are for states of matter and other things within chemical notation I think.

### Re: Denoting brackets/parentheses

Posted: Sun Jan 13, 2019 2:44 pm
Brackets are for concentration and parentheses are for states of matter and other things within chemical notation I think.

### Re: Denoting brackets/parentheses

Posted: Sun Jan 13, 2019 10:22 pm
Brackets are primarily used to denote that the element is in concentration, parentheses are just used for partial pressures.

### Re: Denoting brackets/parentheses

Posted: Mon Jan 14, 2019 12:18 am
You would use the brackets to denote concentrations or molarity and use parentheses to indicate partial pressure

### Re: Denoting brackets/parentheses

Posted: Mon Jan 14, 2019 9:32 am
Brackets are only used when dealing with concentration.

### Re: Denoting brackets/parentheses

Posted: Mon Jan 14, 2019 1:50 pm
Brackets are typically used to denote concentration!