Ashiny, gold-colored bar of metal weighing
57.3 g has a volume of 4.7 cm. is the bar of metal
pure gold?

No it is not of pure gold.

Explanation:

Density is defined as the mass contained per unit volume.  It is characteristic of a material.

Given : Mass of gold = 57.3 grams

Volume of gold =

Putting in the values we get:

Density of pure gold =

Thus as the density of the material is less as compared to density of pure gold, thus it is not pure gold.

8 carbon atoms forming single bonds with 18 hydrogen atoms; a triple bond exists between the third and fourth carbon atom from the right

explanation:

the earth would become to overheated and everything alive on it will eventually die from overheating. plants will eventually die as well, water will evaporate, and it will be nothing but a hot planet without anything living on it.