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### K units

Posted: Tue Jan 14, 2020 11:52 pm
Why are units omitted when calculating K?

### Re: K units

Posted: Wed Jan 15, 2020 12:00 am
Explaining in a non-chemistry way, K is the ratio of products over reactants. And ratios are just numbers; they don't have units.

### Re: K units

Posted: Wed Jan 15, 2020 2:43 am
K is a unitless quantity, because it's just a ratio of product over reactants. This also goes into the concept of activities (but that hasn't been really gone over in depth yet)

### Re: K units

Posted: Wed Jan 15, 2020 8:07 am
The equilibrium constant is actually the activity of the product divided by the activity of the reactant. Calculating the activity is its own separate equation, but in that equation the units actually cancel. Therefore, the activity of the products and reactants have no units making K have no units too.

### Re: K units

Posted: Wed Jan 15, 2020 9:21 am
K is a constant

### Re: K units

Posted: Wed Jan 15, 2020 10:28 pm
For the purpose of this class, K is unitless. But in higher classes, it refers to the "activity" of the reactants and products.

### Re: K units

Posted: Wed Jan 15, 2020 10:45 pm
When you are looking for K is is molarity over molarity, which can cancel out all units. And if it doesn't cancel out all units, imagine the reactants changing to products or products changing to reactancts as activity, and activity is unitless.

### Re: K units

Posted: Thu Jan 16, 2020 12:44 pm
K is simply a ratio not a unit of measure

### Re: K units

Posted: Thu Jan 16, 2020 1:21 pm
K actually measures the activity of the reaction. For this class, I think we omit the units for simplicity

### Re: K units

Posted: Thu Jan 16, 2020 1:28 pm
I think it's because K is an activity and activities don't have units.

### Re: K units

Posted: Thu Jan 16, 2020 1:32 pm
K is just a number that is used to show the ratio of products to reactants. I dont think K is ever used in equations so it doesnt need units anyways