Rate Of A Chemical Reaction

The given reaction is,



So,

Let's evaluate each option for the possibility of a chemical reaction:
1. Gold ornaments are washed with dil. HCl: - Gold (Au) is a noble metal and does not react with dilute hydrochloric acid (HCl). Therefore, no chemical reaction will occur in this case.
2. ZnSO (aq) is placed in a copper vessel:
Zinc sulfate (ZnSO ) is an aqueous solution, and copper is less reactive than zinc. When zinc sulfate solution is placed in a copper vessel, no reaction occurs between zinc sulfate and the copper vessel. However, if the copper vessel was placed in a more reactive metal, such as zinc, a reaction could occur. But in this case, the metal zinc is reacting with the copper solution.
3. AgNO solution is stirred with a copper spoon:
Copper (Cu) is more reactive than silver (Ag), so when AgNO solution is stirred with a copper spoon, copper will displace silver from silver nitrate, forming copper nitrate and silver. The reaction is: Therefore, a chemical reaction is possible.
4. Conc. HNO is stored in a platinum vessel:
Platinum is an inert metal and does not react with concentrated nitric acid (HNO ). Therefore, no reaction occurs in this case.

Thus, the correct answer is (B) ZnSO (aq) is placed in a copper vessel, as it is the only option where a chemical reaction is possible.

Determine the Reaction with Rate Constant Units of

We need to identify which of the following reactions has a rate constant with units of :

Options:

1. (A) Acid catalysed hydrolysis of
2. (B)
3. (C)
4. (D) Decomposition of on the surface of Gold

Analysis:

The unit corresponds to a second-order reaction with respect to concentration.

Option (A):

Typically, acid catalysed hydrolysis reactions are first order with respect to the ester and first order with respect to the acid catalyst. Thus, the rate constant would have units of or .

Option (B):

This reaction is a second-order reaction with respect to . Thus, the rate constant would have units of .

Option (C):

This reaction is a second-order reaction with respect to and first order with respect to . Thus, the rate constant would have units of .

Option (D):

The decomposition of on a surface is typically a first-order reaction. However, if it occurs on a surface, the rate constant is often expressed in terms of surface area, not concentration. This could potentially lead to a rate constant with units of if the surface area effects are normalized to concentration units.

Conclusion:

Based on the analysis, the most likely answer is (D) Decomposition of on the surface of Gold, as it could potentially have a rate constant with units of under certain conditions.