<u>Answer:</u> The percentage abundance of
isotope is 69 %.
<u>Explanation:</u>
Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.
Formula used to calculate average atomic mass follows:
.....(1)
We are given:
Let the fractional abundance of
isotope be 'x'
- <u>For
isotope:</u>
Mass of
isotope = 62.93 amu
Fractional abundance of
isotope = x
- <u>For
isotope:</u>
Mass of
isotope = 64.93 amu
Fractional abundance of
isotope = (1-x)
- Average atomic mass of copper = 63.55 amu
Putting values in above equation, we get:
![63.55=[(62.93\times x)+(64.93\times (1-x))]\\\\x=0.69](https://tex.z-dn.net/?f=63.55%3D%5B%2862.93%5Ctimes%20x%29%2B%2864.93%5Ctimes%20%281-x%29%29%5D%5C%5C%5C%5Cx%3D0.69)
Converting this fractional abundance into percentage abundance by multiplying it by 100, we get:
![\Rightarrow 0.69\times 100=69\%](https://tex.z-dn.net/?f=%5CRightarrow%200.69%5Ctimes%20100%3D69%5C%25)
Hence, the percentage abundance of
isotope is 69 %.
Atoms, the main constituents of matter, consist of positively charged protons and neutral neutrons within a nucleus which are surrounded by a sea of electrons that sit in distinct shells. The electrons on the outer shell are known as valence electrons. The valence can be descibed as the smaller number of electrons an atom has to borrow or to lend, the greater the activity.
The answer is B.
it is less dense then cold
Answer:
A and B
Explanation:
Graphite (like in a pencil) is a material that can easily be smudged and shaded just by smudging it a little. Therefore I believe it's A or B