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What is the effect of an increase in temperature on the ionization constant, Ka, of a weak acid with an initial concentration of 0.1 M and a pKa of 4.74? If the temperature is increased from 25°C to 35°C, what would be the new value for Ka?

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The ionization constant, Ka, of a weak acid is affected by temperature changes. Generally, an increase in temperature will increase the ionization constant, Ka, for endothermic reactions  reactions that absorb heat , and decrease the ionization constant for exothermic reactions  reactions that release heat . The ionization of a weak acid is typically an endothermic process, so we can expect the Ka value to increase with an increase in temperature.To determine the new value for Ka at 35C, we can use the Van't Hoff equation:ln Ka2/Ka1  = -H/R *  1/T2 - 1/T1 where Ka1 and Ka2 are the ionization constants at temperatures T1 and T2, respectively, H is the standard enthalpy change of the reaction, R is the gas constant  8.314 J/molK , and T1 and T2 are the initial and final temperatures in Kelvin  K .However, we do not have enough information to calculate the new Ka value directly, as we do not know the standard enthalpy change  H  for the ionization of the weak acid in question. If this information were provided, we could use the Van't Hoff equation to calculate the new Ka value at 35C.

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