Effect of heat and orders in rate equations

[aj47]

If a chemical reaction has an order of zero it means the reaction rate can be independant of temperature. This got me thinking and the only reactions i could think of that this was true for was radioactive decay.

What I don't understand is how the rate of a chemical reaction can stay constant under different temperatures.

Surely all molecules gain kinetic energy from heat so therefore all reactions are speeded up by an increase of temperature.

Can someone explain this to me as i'm sure i'm missing out something really fundemental.

thanks.

[woelen]

In fact, all chemical reactions depend on temperature.

This also is true for nuclear reactions, but for them, temperature sensitivity is on a totally different temperature scale. At ordinary temperatures (up to thousands of degrees), the nuclei are shielded effectively and then nuclear reactions are not affected. But at tens of millions or hundreds of millions of degrees there certainly is a dependence on temperature, just as there is in the range of hundreds of Kelvin for ordinary chemical reactions.

[aj47]

So using 0 as the rate order is just an approximation?

[some nerd]

rate of reaction zero means independent of concentration. In that case, rate of reaction is proportional to rate constant which depends upon temperature.

[aj47]

ah ok thanks, so no Chemical reactions rate is completly independant of temperature, right?

[5614]

Correct.