The term for a push or pull is called Force.
<span>The </span>elements are arranged<span> in order of increasing atomic number. Vertical columns(called groups) contain </span>elements with similar properties. Horizontal rows called periods elements with<span> the same number of atomic orbitals(That's why Hydrogen and Helium are separated from the rest of the table).
Hope this helps:)</span>
Could you attach a picture because I can tell you didn't post the entire question.
Answer:
Carbon has 4 valence electrons (electrons that are used in bonding), and therefore it can make 4 bonds which is the most one can (other than some exceptions, but in general it is the most). It wants to make 4 bonds so it can reach a full octet of 8 elections, hence the rule of 8.
Explanation:
How many protons does Thorium have? 90
How many neutrons does Thorium-234 have? 144
Calculate the mass defect for the isotope thorium-234 1.85864 amu