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

Carlos Gonzales 1H
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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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Joined: Tue Oct 10, 2017 7:13 am

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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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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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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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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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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