Answer:

Explanation:
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In this case, since these problems about gas mixtures are based off Dalton's law in terms of mole fraction, partial pressure and total pressure, we can write the following for hydrogen, we are given its partial pressure:

And can be solved for the total pressure as follows:

However, we first calculate the mole fraction of hydrogen by subtracting that of nitrogen to 1 due to:

Then, we can plug in to obtain the total pressure:

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1-energy
2- force
3- force
4- force
5- energy
6- energy
The average atomic mass of Boron: 10.431 amu
<h3>Further explanation
</h3>
Isotopes are atoms whose no-atom has the same number of protons while still having a different number of neutrons.
So Isotopes are elements that have the same Atomic Number (Proton)
Atomic mass is the average atomic mass of all its isotopes
In determining the mass of an atom, as a standard is the mass of 1 carbon-12 atom whose mass is 12 amu
Mass atom X = mass isotope 1 . % + mass isotope 2.% + ...
The average atomic mass of boron :

Answer:
they had killed other animals
Answer:
Electrons
Explanation:
Cathode rays carry electronic currents through the tube. Electrons were first discovered as the constituents of cathode rays. J.J. Thomson used the cathode ray tube to determine that atoms had small negatively charged particles inside of them, which he called “electrons.”