## Negative sign in reactants

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

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Carlos Gonzales 1H
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### Negative sign in reactants

For the general rate law, will the reactants always have a negative sign in front of them? Is this simply because the reactants are being decomposed?

Hazem Nasef 1I
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### Re: Negative sign in reactants

The reaction rate is represented as change in concentration over change in time. Since the concentration of reactants decreases as time goes on, the change in concentration is a negative value. To make the reaction rate a positive value, we always place a negative sign in front of the change in concentration of reactants.

204918982
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### Re: Negative sign in reactants

There will always be a negative sign in front of the reactants in order to make the reaction rate positive

Yu Chong 2H
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### Re: Negative sign in reactants

Yes because the reactants would be decreasing, to get a positive value for rate of reaction we have to have a negative sign ahead of it.

Leah Thomas 2E
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### Re: Negative sign in reactants

You can also think of it as reactants being used up so it's rate is negative since the amount is declining.

Sandhya Rajkumar 1C
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### Re: Negative sign in reactants

The concentration of the reactants will decrease over the reaction, so without the negative sign, the reaction rate for the reactants would be a negative number, as it is calculated from the change in concentration over the change in time. However, we want to work with positive reaction rates, so by adding a negative sign in front of the change in concentration of the reactants, we make the reaction rate positive.

Varsha Sivaganesh 1A
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### Re: Negative sign in reactants

Since we are calculating the rate of the forward reaction, we are assuming that the reactants are being used up and converted into the products. Therefore, the concentration of reactants is decreasing and the change in concentration will be negative.

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