Answer:
The answer for 17 is maybe
What about? You must provide a question :)
Answer:
151.94 u
Explanation:
The atomic mass of Eu is the <em>weighted average</em> of the atomic masses of its isotopes.
We multiply the atomic mass of each isotope by a number representing its relative importance (i.e., its <em>percent abundance</em>).
The atomic masses of Eu-151 and Eu-153 are 150.92 u and 152.92 u, respectively.
Set up a table for easy calculation.
0.4803 × 150.92 u = 72.472 u
0.5197 × 152.92 u = <u> 79.473 u
</u>
TOTAL = 151.94 u
Group 6 elements usually have extra electrons to make give them an octet. So, they have 6 electrons to start and when they have an octet, they have 8.
We can find the charge by doing simple math 6 - 8 = -2
Answer is D)
Electromagnetic wave travels faster through air than metal.
Option A
<u>Explanation:</u>
There are different kinds of wave energy. The most significant are electromagnetic and mechanical waves. The mechanical waves propagate through the medium by transfer of energy by vibrating of particles in medium.
So, the more number of particles present in the medium, the more fast the mechanical wave can propagate. So the mechanical waves travel faster in metals consisting of more number of free charge carriers. But electromagnetic waves does not need any of the medium to propagate. So it can travel faster in air than in metals.
