When 100ml of M HCl is mixed with 100ml of N NaOH, the pH of the resulting solution is a. 1
b. 4
c. 6
d. 7​

Option d. 7

Explanation:

A mixture of a strong base and a strong acid produce a neutral salt and water.

This is the reaction of neutralization:

HCl + NaOH → NaCl + H₂O

NaCl →  Na⁺  +  Cl⁻

Sodium chloride is neutral salt which does not give H⁻ neither OH⁻ to medium, that's why pH is neutral.

Both ions are derivated from a strong acid and base so they do not make hydrolisis. They are a conjugate pair of a weak acid and base. The reactions can not occur:

Cl⁻  +  H₂O ← OH⁻  +  HCl

Na⁺  +  H₃O⁺ ← NaOH  + H₂O

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.