Raw milk sours in about 4 h at 27° C, but in about 48 h in a refrigerator at 17° C. What is the activation energy for souring of milk?

Question

Raw milk sours in about 4 h at 27° C, but in about 48 h in a refrigerator at 17° C. What is the activation energy for souring of milk? (A) 78.3 kJ mol -1 (B) 46.21 kJ mol -1 (C) 23.5 kJ mol -1 (D) 80.8 kJ mol -1

Tardigrade Admin · Accepted Answer

K propto (1/t) log (k2/k1) = log (t1/t2)=(Ea/R)((T2-T1/T1 ⋅ T2)) log (48/4) =(Ea/8.314)((10/300 × 290)) Ea =78.0 kJ mol -1

Q. Raw milk sours in about $4 h$ at $2 7^{\circ} C$ , but in about $48 h$ in a refrigerator at $1 7^{\circ} C$ . What is the activation energy for souring of milk?

$78.3 k J m o l^{- 1}$

$46.21 k J m o l^{- 1}$

$23.5 k J m o l^{- 1}$

$80.8 k J m o l^{- 1}$

$K \propto \frac{1}{t}$
$lo g \frac{k _{2}}{k _{1}} = lo g \frac{t _{1}}{t _{2}} = \frac{E _{a}}{R} (\frac{T _{2} - T _{1}}{T _{1} \cdot T _{2}})$
$lo g \frac{48}{4} = \frac{E _{a}}{8.314} (\frac{10}{300 \times 290})$
$E_{a} = 78.0 k J m o l^{- 1}$

Q. Raw milk sours in about 4h at 27∘C, but in about 48h in a refrigerator at 17∘C. What is the activation energy for souring of milk?

78.3kJmol−1

46.21kJmol−1

23.5kJmol−1

80.8kJmol−1