The reactant concentration in a zero-order reaction was 5.00×10−2 M after 195 s and 2.50×10−2 M after 385 s . What is the rate constant for this reaction? Express your answer with the appropriate units. Indicate the multiplication of units, as necessary, explicitly either with a multiplication dot or a dash.

Answer : The rate constant for this reaction is,

Explanation :

To calculate the rate constant for zero order reaction, the expression used is:

where,

= initial concentration

= final concentration = at 195 s

= final concentration = at 385 s

k = rate constant = ?

Now put all the given values in the above expression, we get:

      ............(1)

and,

       ............(2)

Subtracting 1 from 2, we get:

Therefore, the rate constant for this reaction is,

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.