Answer:
Magnesium and calcium belong to the second group i. e. alkaline earth metals. They are known as earth metals because they are extracted from the earth. They are very reactive elements. Their reactivity increases when we go from top to bottom because the outermost electrons goes farther from the nucleus i. e. atomic radius increases so less energy is needed for its removal.
Answer:
b) O₂
d) CH₄
Explanation:
In a chemical equation, the <u>reactants</u> are the substances that are written on the <u>left side</u>. The reactants react to produce the products. On the right side, the products are written.
The arrow => is used to separate the reactants from the products.
To the left of the arrow, you can see this written:
CH₄ + 2O₂
The plus sign + is used to separate each reactant.
In 2O₂ you can ignore the big 2 because it is a coefficient, which is written to balance the equation.
The reactants are CH₄ and O₂
A. Raccoons. They will be able to survive in a housing area just as well, or even better then they had in the forrest.
I hope that helped! :D
Explanation:
It is known that charge on xenon nucleus is
equal to +54e. And, charge on the proton is
equal to +e. So, radius of the nucleus is as follows.
r = 
= 3.0 fm
Let us assume that nucleus is a point charge. Hence, the distance between proton and nucleus will be as follows.
d = r + 2.5
= (3.0 + 2.5) fm
= 5.5 fm
=
(as 1 fm =
)
Therefore, electrostatic repulsive force on proton is calculated as follows.
F = 
Putting the given values into the above formula as follows.
F = 
= 
= 
= 411.2 N
or, =
N
Thus, we ca conclude that
N is the electric force on a proton 2.5 fm from the surface of the nucleus.
Answer:
-1, -4
Explanation:

Factoring, you get:

To find what x can be, you need to realize what could make this equation true. To set the left side equal to 0, either one of the terms in parentheses must be equal to 0. To do that, x must be the negative of the other term, so that they can cancel each other out. Therefore, x is -4 and -1. Hope this helps!