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Rate constant k varies with temperature ...

Rate constant k varies with temperature T(k) as given by equation
`logk=logA-(E_(a))/(2.303RT)`
A plot between log k and `(1)/(T)` is straight line from the graph we can say

A

`E_(a)=2.303Rxx"slope"`

B

`E_(a)=2.303R^(2)xxtantheta`

C

`E_(a)=Rtantheta`

D

None of these

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the relationship between the rate constant \( k \) and temperature \( T \) as given by the equation: \[ \log k = \log A - \frac{E_a}{2.303RT} \] we can follow these steps: ### Step 1: Identify the equation form The equation resembles the linear form \( y = mx + c \), where: - \( y \) is \( \log k \) - \( m \) is the slope of the line, which is \(-\frac{E_a}{2.303R}\) - \( x \) is \(\frac{1}{T}\) - \( c \) is \(\log A\) ### Step 2: Understand the slope From the equation, we can see that the slope of the line plotted between \( \log k \) and \(\frac{1}{T}\) is equal to \(-\frac{E_a}{2.303R}\). This indicates that the slope is negative, which implies that as the temperature increases (and thus \(\frac{1}{T}\) decreases), the value of \(\log k\) increases. ### Step 3: Relate slope to activation energy Since the slope is related to the activation energy \( E_a \), we can express the activation energy as: \[ E_a = -\text{slope} \times 2.303R \] ### Step 4: Conclusion From the graph, we can conclude that the activation energy \( E_a \) can be determined from the slope of the line. The negative slope indicates that the activation energy is a positive quantity, which is consistent with the physical interpretation of activation energy in chemical kinetics. ### Final Answer Thus, from the graph, we can say that the activation energy \( E_a \) can be calculated using the slope of the line obtained from the plot of \( \log k \) versus \(\frac{1}{T}\). ---

To solve the question regarding the relationship between the rate constant \( k \) and temperature \( T \) as given by the equation: \[ \log k = \log A - \frac{E_a}{2.303RT} \] we can follow these steps: ...
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