50 POINTS Which of the following correctly describes a compound?

A. The atoms are bonded together, and the compound has different physical and chemical properties than the individual elements.
B. The atoms have no set ratio for how the atoms can combine, and they are not chemically bonded together.
C. The atoms can only combine in fixed ratios, and they retain their individual chemical and physical properties.
D. The atoms retain their individual chemical properties, and they can only be separated from each other by a chemical change.

c no option is the correct one

A chemical compound can be described as substance composed of atoms from more than one element held together by chemical bonds in a fixed stoichiometric proportion. A compound has different physical and chemical properties from its constituent elements.

For example : compound water is made up of H and O bonded together and it has different properties from O and H.

Thus, among the given options, the one coreectly describing a compound is

a) The atoms are bonded together, and the compound has different physical and chemical properties than the individual elements.

76 mmHg is the partial pressure of oxygen on this new planet.

Explanation:

Atmospheric pressure on air on earth = 760 mmHg

On an unknown planet :

Oxygen makes up 10% of the atmosphere.

The mole fraction of oxygen gas can be written as =

Carbon dioxide makes up 15% of the atmosphere.

The mole fraction of carbon dioxide gas can be written as =

Nitrogen makes up the remaining 75% of the atmosphere.

The mole fraction of nitrogen gas can be written as =

Atmospheric pressure of air on unknown planet,p= 760 mmHg (given)

Partial pressure of gases can be calculated by the help o Dalton's law of partial pressure:

Partial pressure of oxygen gas :

Partial pressure of carbon dioxide gas :

Partial pressure of nitrogen gas :