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The uncoiling of DNA is a 1st order process with an activation energy of about 420 kJ/mol. The half-life at 50 °C is 2 minutes. What is the half-life at normal body temperature, 37 °C?

a. 1.42 min
b. 2.86 min
c. 4.75 min
d. 6.21 min

User Mr Tarsa
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1 Answer

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Final answer:

The half-life at 37°C is approximately 1.42 minutes.

Step-by-step explanation:

The half-life of a 1st order process can be calculated using the equation:

ln(Nt/N0) = -kt

Where Nt is the final concentration, N0 is the initial concentration, t is time, and k is the rate constant. We can rearrange this equation to solve for the half-life:

t1/2 = (ln2)/k

Given that the activation energy is 420 kJ/mol and the half-life at 50°C is 2 minutes, we can use the Arrhenius equation:

k = Ae^(-Ea/RT)

Where A is the pre-exponential factor, Ea is the activation energy, R is the gas constant (8.314 J/mol·K), and T is the temperature in Kelvin. By substituting the given values, we can find the rate constant at 50°C. Using this rate constant, we can then calculate the half-life at 37°C.

By plugging in the values and performing the calculations, the half-life at 37°C is approximately 1.42 minutes.

User Euphemia
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