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а А(gas) + b В(gas) = с С(gas) + d D(gas)
а
υ = k · [А] · [В] b
For a heterogeneous reaction the concentration of the solid phase is not included in
the expression for the reaction rate:
а А(solid) + b В(gas) = с С(gas) + d D(gas)
υ = k · [В] b
The influence of temperature on the chemical reaction rate is determined
by the van’t Hoff equation:
When the temperature increases by 10 ºС the rate of any chemical reaction
increases by 2-3 times. The number which indicates how many times the reaction
rate increases with an increase of temperature by 10 °C is called the temperature
coefficient of the reaction γ.
t
10
t t
2 1
7.3. Chemical equilibrium
Chemical equilibrium is the state of the system, when the direct reaction velocity
equals the speed of the reciprocal reaction. In this case one can determine the
constant of the chemical equilibrium (K). For a homogeneous reaction in general
form
а А + в В ↔ с С + d D
c
d
C
D
К =
рівн a b
B
A
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