Explanation:
The given data is:
The half-life of gentamicin is 1.5 hrs.
The reaction follows first-order kinetics.
The initial concentration of the reactants is 8.4 x 10-5 M.
The concentration of reactant after 8 hrs can be calculated as shown below:
The formula of the half-life of the first-order reaction is:

Where k = rate constant
t1/2=half-life
So, the rate constant k value is:

The expression for the rate constant is :

Substitute the given values and the k value in this formula to get the concentration of the reactant after time 8 hrs is shown below:

Answer: The concentration of reactant remains after 8 hours is 2.09x10^-6M.
Answer:
The molecular formula of the compound is
. The molecular formula is obtained by the following expression shown below

Explanation:
Given molecular mass of the compound is 176 g/mol
Given empirical formula is
Atomic mass of carbon, hydrogen and oxygen are 12 u , 1 u and 16 u respectively.
Empirical formula mass of the compound = 


Molecular formula = 4
Molecular formula is 
Answer:
the answer has been given below have a good day
Explanation:
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