Answer:
A
Explanation:
particles are frozen and hence will vibrate in their fixed positions
Answer:
Percentage abundance of B 10 is = 20 %
Percentage abundance of B 11 is = 80 %
Explanation:
The formula for the calculation of the average atomic mass is:
Given that:
Since the element has only 2 isotopes, so the let the percentage of first be x and the second is 100 -x.
For first isotope, B 10:
% = x %
Mass = 10.0129 u
For second isotope, B 11:
% = 100 - x
Mass = 11.0093 u
Given, Average Mass = 10.81 u
Thus,

Solving for x, we get that:
x = 20 %
Thus percentage abundance of B 10 is = 20 %
Percentage abundance of B 11 is = 100 - 20 % = 80 %
Answer:
A
Explanation:
The lower mantle is under the surface of the earth while the ocieanic crust is above the surface
Answer:
the answer is 3.33⋅1023 molecules of Cl2. Note that 6.022⋅1023 is also known as Avogadro's number, and it can be referred to as the number of molecules in one mole of that substance. Also, I calculated 70.9 because 35.45 g/mol (the mass of one Chlorine atom) times 2 is 70.9 g/mol (Cl2 has two Chlorine atoms).
Explanation: