When an ion is formed, the number of protons does not change. By removing an electron from this atom we get a positively charged Na+ ion that has a net charge of +1. Atoms that gain extra electrons become negatively charged. A neutral chlorine atom, for example, contains 17 protons and 17 electrons
Answer:

Explanation:
The formula of density is:

If the formula is rearranged for volume, it becomes:

The mass of the platinum is 38.5 grams.
The density is 21.5 grams per cubic centimeter.

Substitute the values into the formula.

Divide. Note that the grams (g) will cancel each other out.

Round to 2 decimal places (hundredth place). The 0 in the thousandth place tells us to leave the 9 in the hundredth place.

The volume is about <u>1.79 cubic centimeters.</u>
Answer:
Explanation:
Magnesium when it oxidizes has a valence of 2.
Oxygen, when it mixes with something, has a valence of - 2
So Mg and O2 will form something, but what? The answer is MgO
Mg + O2 ===> MgO
To balance this equation, you need 2 Magnesiums on the right and 2 Oxygens also on the right. The left will need a two Magnesiums.
The balanced equation will be
2Mg + O2 ====> 2MgO
I’m am most positive the answer is c. For cat
We can find the principal level or lower level
using Rydberg's formula:
1/w = R(1/L² - 1/U²)
<span>where:</span>
<span>w is the
wavelength (93.8 nm),</span>
L is the lower energy level (unknown)
U the upper energy level (n= 6)
R is Rydberg's constant (10,967,758
waves per meter)
Substituing known values into the equation:<span>
1/(9.38 * 10^-8 m.) = 10,967,758(1/L² - 1-36) </span>
Using the solver function of the calculator to
get for L:
L = 0.999 <span>
so L = 1.
<span>The lower level is 1 (the ground state).</span></span>