This question uses weighted averages.
Since the average mass of element A is 63.6 amu and the only two isotopes are 63 and 65,
63.6 = x% * 63 + (1-x%) * 65
If you don't want to calculate this (like me), you can look at the answer choices.
If it was 100% A-63, the weight would be 63. Cross off D.
If it was 50/50, the weight would be 64. Cross off C.
So since the weighted average is 63.6, you would expect there to be more A-63 than A-65, so B is the only answer that makes sense.
Answer: A. Energy was absorbed
Answer: D
Explanation:
because mold is a chemical reaction with with the air that's why the put a date cause the bread can only last for so long in till the chemical reaction.But D is is right because your body has to go though a chemical reaction in or to digest it and and break it down even more.So D would be the right answer cause that's where most of your chemical reaction happens when food is swallowed into the stoamch i hope i was able to explain it as much as i can
Energy lost to condense = 803.4 kJ
<h3>Further explanation</h3>
Condensation of steam through 2 stages:
1. phase change(steam to water)
2. cool down(100 to 0 C)
1. phase change(condensation)
Lv==latent heat of vaporization for water=2260 J/g
2. cool down
c=specific heat for water=4.18 J/g C
Total heat =
