Answer:
a. K⁺
b. Se²⁻
Explanation:
Isoelectronic species are those that have the same number of electrons.
a.
Ar has 18 electrons. K has 19 electrons, so when it loses 1 electron to form K⁺, it is isoelectronic with Ar.
b.
Kr has 36 electrons. Se has 34 electrons, so when it gains 2 electrons to form Se²⁻, it is isoelectronic with Kr.
Answer:
The depth of the damage is given as 
Explanation:
From Fick's second law
![\frac{C_{x}-C_{0}}{C_{s}-C_{0}} = 1 -erf [\frac{x}{2\sqrt{Dt} } ] ...(1)](https://tex.z-dn.net/?f=%5Cfrac%7BC_%7Bx%7D-C_%7B0%7D%7D%7BC_%7Bs%7D-C_%7B0%7D%7D%20%3D%201%20-erf%20%5B%5Cfrac%7Bx%7D%7B2%5Csqrt%7BDt%7D%20%7D%20%5D%20...%281%29)
Where
is the temperature when the skin is damage
is the initial temperature of the skin
is the temperature of the oven
erf is a mathematical function known as error function
D is the thermal diffusivity
x is the depth of the damage
From the question we are given that
= 62°C
= 33°C
D = 
Substituting values into equation one
![\frac{62-33}{200-33} = 1 -erf [\frac{x}{2\sqrt{2.5*10^{-7}} *2} ]](https://tex.z-dn.net/?f=%5Cfrac%7B62-33%7D%7B200-33%7D%20%3D%201%20-erf%20%5B%5Cfrac%7Bx%7D%7B2%5Csqrt%7B2.5%2A10%5E%7B-7%7D%7D%20%2A2%7D%20%5D)
![erf[\frac{x}{1.414*10^{-3}} ] = 0.826\\](https://tex.z-dn.net/?f=erf%5B%5Cfrac%7Bx%7D%7B1.414%2A10%5E%7B-3%7D%7D%20%5D%20%3D%200.826%5C%5C)
Let assume that 
Hence

Looking at the table of error function shown on the first uploaded image
We can use interpolation to obtain the value of z in this manner
z = 0.96
Substituting the value of z into equation 2


Answer:
The volume indicated would be closest to 9.16
Am so sorry I don’t know how to help you hope you find the answer