Atomic mass of Br = 79.904
<span>Now lets say y% is abundance of 79Br. </span>
<span>Then abundance of 81Br = (100 - y) </span>
<span>mass due to 79Br = 78.9183 * y/100 = 0.789183y
</span><span>mass due to 81Br = 80.9163 x (100 - y)/100 = 0.809163(100 - y) </span>
<span>Therfore</span>
<span>0.789183y+ 0.809163(100 - y) = 79.904 </span>
<span>0.789183y + 80.9163 - 0.809163y = 79.904 </span>
<span> - 0.01998y= 79.904 - 80.9163
= - 1.0123 </span>
<span>y = 1.0123/0.01998 = 50.67% </span>
<span> 79Br = 50.67% </span>
<span>now
81Br = 100 - 50.67 = 49.33%
hope this helps</span>
The reasonable ground-state electron configuration is: 1s2 2s2 2p6 3s2 3p6 4s2 4d8
1. x-ray soft tissue organs - barium
2. reduce pain and fever- acetylsalicylic acid
3. anesthetic- nitrous oxide
4. treat acne - A. benzoyl peroxide
Answer:
A compound
Explanation:
It is a compound because two elements combined together dont make an element, a substance is also not it ans neither is a solution. It is A compound because compounds are combinations of two or more elements.
Answer: Option (a) is the correct answer.
Explanation:
The given data is as follows.
= 4.19 
= 1.9 
Heat of vaporization (
) at 1 atm and
is 2259 kJ/kg
= 0
Therefore, calculate the enthalpy of water vapor at 1 atm and
as follows.
=
+
= 0 + 2259 kJ/kg
= 2259 kJ/kg
As the desired temperature is given
and effect of pressure is not considered. Hence, enthalpy of liquid water at 10 bar and
is calculated as follows.
= 
= 334.781 kJ/kg
Hence, enthalpy of water vapor at 10 bar and
is calculated as follows.

=
= 2410.81 kJ/kg
Therefore, calculate the latent heat of vaporization at 10 bar and
as follows.
=
= 2410.81 kJ/kg - 334.781 kJ/kg
= 2076.029 kJ/kg
or, = 2076 kJ/kg
Thus, we can conclude that at 10 bar and
latent heat of vaporization is 2076 kJ/kg.