Answer:
A: Helium or Hydrogen
Explanation:
Terrestrial planets are the 4 inner most planets of the solar system which are mercury, venus, earth, Mars, while the giant planets are the 4 outer most which are Jupiter, Saturn, Uranus and Neptune.
Now, these outer most ones are the surface ones and are surrounded primarily by layers of hydrogen and helium gases.
Given the data from the question, the identity of the unknown metal having a of mass 133 g is Cobalt
<h3>What is density? </h3>
The density of a substance is simply defined as the mass of the subtance per unit volume of the substance. Mathematically, it can be expressed as
Density = mass / volume
<h3>How to determine the density </h3>
- Mass = 133 g
- Volume of water = 25 mL
- Volume of water + metal = 40 mL
- Vol of metal = 40 – 25 = 15 mL
Density = mass / volume
Density = 133 / 15
Density = 8.86 g/mL
Comparing the density of the unknown metal (i.e 8.86 g/mL) with those given in the chart in the question above, we can conclude that the unknown metal is Cobalt
Learn more about density:
brainly.com/question/952755
Answer:
electrons move around the nucleus in fixed orbits of equal amounts of energy
Explanation:
Quantum Theory