Answer:
The air in the atmosphere consists of nitrogen, oxygen, which is the life-sustaining substance for animals and humans, carbon dioxide, water vapour and small amounts of other elements (argon, neon, etc.). Higher in the atmosphere air also contains ozone, helium and hydrogen.
Atomic mass of boron = 10.81
<h3>What are Isotopes?</h3>
Isotopes are variants of a particular element in which they have the same number of protons but differ in the number of neutrons in the atom.
So, here as we said we have isotopes which weigh 10.01 and 11.01.
Given,
relative abundance of B-10 = 10.1 amu
relative abundance of B- 11 = 11.01 amu
percentage of B-10 = 20%
percentage of B-11 = 80%
Then the relative atomic mass depends upon the relative abundance of various isotopes of that particular element. Suppose an element consists of two isotopes and average atomic mass is equal to
(Relativeabundance(1)×Atomicmass(1)+Relativeabundance(2)×Atomicmass(2)) / (Relativeabundance(1)+Relativeabundance(2))
Atomic mass of boron = (20 × 10.01 + 80 × 11.01) / (80 + 20 )
= 1081/100
= 10.81
To learn more about atomic mass from the given link
brainly.com/question/3187640
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Answer: loss of electrons
Explanation:
An atom is made up of three subatomic particles named protons neutrons and electrons. An atom forms positive ion with the loss of at least one electron.
For instance: Calcium with atomic number 20, and electronic configuration 1s2, 2s2 2p6, 3s2 3p6, 4s2 will lose the two outermost electrons to form a divalent positive ion (Ca2+).
Ca --> Ca2+ + 2e-
Thus, loss of electrons is the change to an atom that occurs when it forms a positive ion
