Answer:
52.9 KJmol-1
Explanation:
From;
log(k2/k1) = Ea/2.303 * R (1/T1 - 1/T2)
The temperatures must be converted to Kelvin;
T1 = 25° C + 273 = 298 K
T2= 35°C + 273 = 308 K
R= gas constant = 8.314 JK-1mol-1
Substituting values;
log 2 = Ea/2.303 * 8.314 (1/298 - 1/308)
Ea = 52.9 KJmol-1
Answer:
A breakdown of the breaking buffer was first listed with its respective component and their corresponding value; then a table was made for the stock concentrations in which the volume that is being added was determined by using the formula
. It was the addition of these volumes altogether that make up the 0.25 L (i.e 250 mL) with water
Explanation:
Given data includes:
Tris= 10mM
pH = 8.0
NaCl = 150 mM
Imidazole = 300 mM
In order to make 0.25 L solution buffer ; i.e (250 mL); we have the following component.
Stock Concentration Volume to be Final Concentration
added
1 M Tris 2.5 mL 10 mM
5 M NaCl 7.5 mL 150 mM
1 M Imidazole 75 mL 300 mM
. is the formula that is used to determine the corresponding volume that is added for each stock concentration
The stock concentration of Tris ( 1 M ) is as follows:
.

The stock concentration of NaCl (5 M ) is as follows:
.

The stock concentration of Imidazole (1 M ) is as follows:
.

Hence, it is the addition of all the volumes altogether that make up 0.25L (i.e 250 mL) with water.
The material that has been widely used in casting has been copper. Thus, option C is correct.
Casting has been the process of molding the liquid into a specific shape with the mold. The casting involves the heating of elements and converting them into liquid. The liquid has been poured into the mold and cooling results in the casted material.
The casted material has been selected based on the boiling temperature, cooling temperature, resistivity, cost-effectiveness, and damping ability.
The material that has been consisted of these characteristics has been copper. Thus, copper has been commonly used for casting. Thus, option C is correct.
For more information about casting, refer to the link:
brainly.com/question/1253405
I think the answer is choice D