What are elements and how do they differ?

Explanation:

Compound

A compound contains atoms of different elements chemically combined together in a fixed ratio.

Compounds contain different elements in a fixed ratio arranged in a defined manner through chemical bonds. They contain only one type of molecule. Elements that compose the compound are chemically combined.

A compound can be separated into simpler substances by chemical methods/reactions.

A huge, virtually limitless, number of chemical compounds can be created. Compounds are classified into molecular compounds, ionic compounds, intermetallic compounds and complexes.

A compound is represented using its chemical formula that represents the symbols of its constituent elements and the number of atoms of each element in one molecule of the compound

Element

An element is a pure chemical substance made of same type of atom.

Elements contain only one type of atom. Each atom has the same atomic number i.e., the same number of protons in their nucleus.

Elements cannot be broken down into simpler substances by chemical reactions.

There are about 117 elements that have been observed. Can be classified as metal, non-metal or metalloid.

An element is represented using symbols.

element is defined as ONE substance. it's a pure substance and contains only oNE type of atom

the answer would be c

a gas, having a molecular weight of 13 kg/kmol and a kinematic viscosity of 0.25 cm2/s, flows through a pipe 0.25 m internal diameter and 5 km long at the rate of 0.4 m3/s and is delivered at atmospheric pressure.