What class is this? (Subject)
The density of the sample is:
Density = mass / volume
Density = 9.85 / 0.675
Density = 14.6 g/cm³
If the sample has 95% gold, and 5% silver, its density should be:
0.95 x 19.3 + 0.05 x 10.5
Theoretical density = 18.9 g/cm³
The difference in theoretical and actual densities is very large, making it likely that the jeweler was not telling the truth.
An atom is the smallest particle of an element that can take part in a chemical reaction.
An atom is made up of energy levels that contain electrons which are negatively charged and the nucleus which contains neutrons and protons that are negatively charge .
Due the positive charge of the nucleus of an atom, an atom always want to attract its electrons and keep them near it however it weakly attracts the other electrons of a nearby atom.
Within the visible range of light, red<span> light waves are scattered the least by atmospheric gas molecules. So at sunrise and </span>sunset, when the sunlight travels a long path through the atmosphere to reach our eyes, the blue light has been mostly removed, leaving mostly red<span> and yellow light remaining.</span>
C.) iron oxide <span>is responsible for the red color of Mars.
Hope this helps!</span>