Electrons that are in the first energy level (energy level 1) are closest to the nucleus and will have the lowest energy. Electrons further away from the nucleus will have higher energy. An atom's electron shell can accommodate 2n2 electrons, where n is the energy level.

6 0

3 years ago

Suppose that a newly discovered element called centium has 3 isotopes that occure in nature. These are centium -200, centium -20

vodomira [7]

Answer:

The answer to your question is 203.8 g

Explanation:

Data

Average atomic mass = ?

Centium-200

Centium-203

Centium-209

Equal amounts

Process

1.- Determine the abundance of each isotope.

If they are in equal amounts in nature, just divide 100 by 3

100/3 = 33.33 % or 0.333

2.- Determine the Average atomic mass

Average atomic mass = Atomic mass 1 x abundance + Atomic mass 2 x

abundance + Atomic mass 3 x abundance

- Substitution

Average atomic mass = 200 x 0.333 + 203 x 0.333 + 209 x 0.333

- Simplification

Average atomic mass = 66.6 + 67.6 + 69.6

Result

Average atomic mass = 203.8 g

3 0

3 years ago

a) Diamond and graphite are two different forms of pure elemental carbon with densities of 3.51 g/cc and 2.25 g/cc respectively.

dybincka [34]

Density can be calculated using the following rule:
density = mass / volume
Therefore,
volume = mass / density

For diamond:
we have mass = 0.5 grams and density = 3.51 g / cm^3
Substituting in the rule, we can calculate the volume of diamond as follows:
volume = 0.5 / 3.51 = 0.14245 cm^3

For graphite:
we have mass = 0.5 grams and density = 2.25 g / cm^3
Substituting in the rule, we can calculate the volume of graphite as follows:
volume = 0.5 / 2.25 = 0.2223 cm^3

8 0

3 years ago