## units

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Posts: 72
Joined: Fri Sep 28, 2018 12:19 am

### units

I got marked down for putting "bar" in my K value on the midterm. Does anyone know why this is?

Ashley Kim
Posts: 62
Joined: Fri Sep 28, 2018 12:19 am
Been upvoted: 1 time

### Re: units

K is a ratio, so it has no units.

Nicolette_Canlian_2L
Posts: 77
Joined: Fri Sep 28, 2018 12:25 am
Been upvoted: 1 time

### Re: units

You would only use bar if the question were to ask, for example, the pressure of the gas at equilibrium.

Selina Bellin 2B
Posts: 62
Joined: Fri Sep 28, 2018 12:25 am

### Re: units

K is unitless

Jeannine 1I
Posts: 73
Joined: Fri Sep 28, 2018 12:27 am

### Re: units

Remember that K is a constant, and therefore has no units(:

Vy Lu 2B
Posts: 59
Joined: Fri Sep 28, 2018 12:24 am

### Re: units

K should not have any units since it is a ratio of concentrations/partial pressures.

Casandra
Posts: 65
Joined: Fri Sep 28, 2018 12:17 am

### Re: units

K doesn't have any units, due to it being a ratio (in which the units cancel)

Desiree1G
Posts: 62
Joined: Fri Sep 28, 2018 12:16 am
Been upvoted: 2 times

### Re: units

Yes remember K does not have a unit because it is a ration and I believe those units cancel out.

LeannaPhan14BDis1D
Posts: 57
Joined: Fri Sep 28, 2018 12:16 am

### Re: units

I did it too and the people above say it's bc k doesn't have units

Celio_G_Dis2C
Posts: 33
Joined: Fri Jan 11, 2019 12:16 am

### Re: units

K is unit less because all units should cancel each other out

Pritish Patil 1K
Posts: 60
Joined: Fri Sep 28, 2018 12:24 am

### Re: units

K does not have units, which is why points were probably taken off for writing bar after k. The units should cancel each other out as well.

Lauren Huang 1H
Posts: 60
Joined: Fri Sep 28, 2018 12:16 am

### Re: units

Although the products and reactants involved in Kp and Kc use units such as molarity and bar, the units cancel out in the end so K is unitless.

Aleeque Marselian 1A
Posts: 60
Joined: Fri Sep 28, 2018 12:24 am

### Re: units

The equilibrium value, K, is a ration of products to reactants, so mathematically the units should cancel out and the calculation would not have units.

RachelCheung1A
Posts: 30
Joined: Fri Sep 28, 2018 12:19 am

### Re: units

The units in K should cancel out so there shouldn't be any units for K.

jocelyntzeng
Posts: 59
Joined: Fri Sep 28, 2018 12:18 am

### Re: units

K is unitless

Jacqueline Duong 1H
Posts: 61
Joined: Fri Sep 28, 2018 12:28 am

### Re: units

it's because there shouldn't be any units for K