## Specific Notation

NatBrown1I
Posts: 62
Joined: Fri Sep 28, 2018 12:17 am

### Specific Notation

Does it matter whether or not when you're calculating K to use this notation [PCl5] or this notation P PCl5 ?

Kristen Kim 2K
Posts: 70
Joined: Fri Sep 28, 2018 12:16 am

### Re: Specific Notation

If PCl5 is aqueous, I would use [PCl5], and if PCl5 is gaseous, use P PCl5. Unless they specify to find partial pressure, I would just use the concentration notation.

2c_britneyly
Posts: 62
Joined: Fri Sep 28, 2018 12:16 am

### Re: Specific Notation

Yes, if you're dealing with a reaction that involves only gases it is more correct to use Pgas, but if you're calculating for a reaction that involves an aqueous solution, you should use hard brackets to indicate Kc.

Sarah Fatkin 4I
Posts: 71
Joined: Fri Sep 28, 2018 12:27 am

### Re: Specific Notation

You should get the same K value regardless of which notation you use; however, partial pressure is usually used for gases and concentration is usually used for solutions. Hope this helps!

Mya Majewski 1L
Posts: 89
Joined: Fri Sep 25, 2015 3:00 am

### Re: Specific Notation

pay attention if the problem gives you Kc or Kp, then you know which to use!

Vicky Lu 1L
Posts: 60
Joined: Fri Sep 28, 2018 12:18 am

### Re: Specific Notation

Notation does matter when calculating K. Use brackets when dealing with concentration such as [PCl5]. Brackets are not require if you write out the value of the concentration of PCl5. As for the gaseous states, you don't not use brackets. If you want, you can use parentheses around P PCl5 like so (P PCl5).