49 neutrons in each nucleus.
<h3>Explanation</h3>
For each nucleus:
Mass number = Number of protons + Number of neutrons.
The atomic number of a nucleus is the same as its number of protons. The atomic number of the nucleus here is 31. There are 31 protons in each nucleus.
- Mass number = 80;
- Number of protons = Atomic number = 31;
- The number of neutrons is to be found.
Again,
Mass number = Number of protons + Number of neutrons.
80 = 31 + Number of neutrons.
Number of neutrons = 80 - 31 = 49.
The most stable isotope would be lead-82.
I think it was sue to she has all the details to seem like it was her
The Triassic period is one of the geological periods and is the shortest of the Mesozoic era. Cambrian is the older era than the Triassic period.
<h3>What is Cambrian and triassic period?</h3>
The Triassic period existed 250 -200 million years ago and started after the vastest and most extreme devastation ever. It is the 1st period of the Mesozoic and is known for the movement of the Dinosaurs on the land, flying pterosaurs and swimming plesiosaurs and ichthyosaurs.
The Cambrian is the period of the Paleozoic era and is the most important period because of the appearance of many animals. In this period, the temperature raised on the planet and the ice sheets melted at a very dangerous rate leading to mass devastation.
Therefore, option A. <u>Cambrian</u> is older than the Triassic period.
Learn more about Cambrian and Triassic periods here:
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the calculated value is Ea is 18.2 KJ and A is 12.27.
According to the exponential part in the Arrhenius equation, a reaction's rate constant rises exponentially as the activation energy falls. The rate also grows exponentially because the rate of a reaction is precisely proportional to its rate constant.
At 500K, K=0.02s−1
At 700K, k=0.07s −1
The Arrhenius equation can be used to calculate Ea and A.
RT=k=Ae Ea
lnk=lnA+(RT−Ea)
At 500 K,
ln0.02=lnA+500R−Ea
500R Ea (1) At 700K lnA=ln (0.02) + 500R
lnA = ln (0.07) + 700REa (2)
Adding (1) to (2)
700REa100R1[5Ea-7Ea] = 0.02) +500REa=0.07) +700REa.
=ln [0.02/0 .07]
Ea= 2/35×100×8.314×1.2528
Ea =18227.6J
Ea =18.2KJ
Changing the value of E an in (1),
lnA=0.02) + 500×8.314/18227.6
= (−3.9120) +4.3848
lnA=0.4728
logA=1.0889
A=antilog (1.0889)
A=12.27
Consequently, Ea is 18.2 KJ and A is 12.27.
Learn more about Arrhenius equation here-
brainly.com/question/12907018
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