## Rate Constant k

$aR \to bP, Rate = -\frac{1}{a} \frac{d[R]}{dt} = \frac{1}{b}\frac{d[P]}{dt}$

Helen Shi 1J
Posts: 78
Joined: Sat Jul 22, 2017 3:00 am

### Rate Constant k

Can someone explain what exactly is the rate constant?

jillian1k
Posts: 54
Joined: Sat Jul 22, 2017 3:00 am

### Re: Rate Constant k

The rate constant k is just an experimentally determined value for a specific reaction at a specific temperature (therefore different reactions have different rate constants). It is also independent of concentration or concentration change. Unless temperature (and/or activation energy) changes, k will remain the same. Therefore, it limits the reaction rate: the higher the k value, the faster the reaction proceeds (therefore making the reaction rate higher).

Grace Han 2K
Posts: 33
Joined: Tue Nov 15, 2016 3:00 am

### Re: Rate Constant k

Also, rate constants are dependent on temperature and activation energy.

Matthew Lee 3L
Posts: 51
Joined: Fri Sep 29, 2017 7:07 am

### Re: Rate Constant k

The rate constant's units are also dependent on the order of the reaction.

Seth_Evasco1L
Posts: 54
Joined: Thu Jul 27, 2017 3:00 am

### Re: Rate Constant k

- As temperature (T) increases, k increases
- As activation energy (Ea) increases, k decreases
- As frequency factor (A) increases, k increases

Mitch Walters
Posts: 45
Joined: Fri Sep 29, 2017 7:07 am

### Re: Rate Constant k

The rate constant is an experimentally determined value for a specific reaction at a specific temperature. It essentially tells you the instantaneous rate of change.

Sarah 2F
Posts: 33
Joined: Fri Sep 29, 2017 7:06 am

### Re: Rate Constant k

instantaneous rate of change