A glass of composition 85% SiO2 - 15% K2O is to be surface strengthened by ion exchange. To this end, two identical specimens approximately the size and shape of credit cards are soaked for the same amount of time at 850degreeC. Sample A is soaked in NaCl and sample B is soaked in KCl. From the list below, select the statements that are true.

a- The yield strength of Sample A will decrease while the yield strength of Sample B will increase.
b- The yield strength of Sample A will increase while the yield strength of Sample B will decrease.
c- The yield strength of both Samples A and B will increase.
d- The yield strength of both Samples A and B will decrease.
e- The yield strength of Sample A will decrease.
f- There will be no change in the yield strength of Sample B.

It's A.

No,its not A. Answer is E and F are the correct answer i think so

It's E

Sorry I meant the last one

The ion exchange process can have different effects on the material properties depending on the ions involved. In this case, Sample A is soaked in NaCl and Sample B is soaked in KCl.

To understand the effect of the ion exchange on the yield strength, we need to consider the chemical composition of the glass and the types of ions involved.

85% SiO2 - 15% K2O composition indicates that the glass contains potassium ions (K+). Soaking Sample A in NaCl will lead to ion exchange, where the sodium ions (Na+) from NaCl replace the potassium ions in the glass.

On the other hand, soaking Sample B in KCl will not involve ion exchange since the glass already contains potassium ions, and adding more potassium ions will not cause a significant change in the material properties.

Now, let's evaluate the given statements:

a- The yield strength of Sample A will decrease while the yield strength of Sample B will increase. - This statement is true. Ion exchange with sodium ions (Na+) in Sample A will lead to a decrease in yield strength, while no significant change is expected in Sample B as it already contains potassium ions.

b- The yield strength of Sample A will increase while the yield strength of Sample B will decrease. - This statement is false. Ion exchange with sodium ions (Na+) is expected to decrease the yield strength of Sample A.

c- The yield strength of both Samples A and B will increase. - This statement is false. While it is possible for the yield strength to increase due to other factors, specifically related to ion exchange, there will be a decrease in yield strength for Sample A.

d- The yield strength of both Samples A and B will decrease. - This statement is false. Sample B is not undergoing significant ion exchange, so its yield strength is expected to remain relatively unchanged.

e- The yield strength of Sample A will decrease. - This statement is true. Ion exchange with sodium ions (Na+) is expected to decrease the yield strength of Sample A.

f- There will be no change in the yield strength of Sample B. - This statement is true. Since Sample B is already soaked in KCl, which has potassium ions (K+), there won't be a significant change in its yield strength.

Therefore, the correct statements are:
a- The yield strength of Sample A will decrease while the yield strength of Sample B will increase.
f- There will be no change in the yield strength of Sample B.