The answer to your question is false
Dry air is a mixture of nitrogen, oxygen, carbon dioxide etc.
air is a mixture of gases 78% nitrogen an 21% oxygen and other components.
B is the correct answer.
The exosphere is the outermost region of the atmosphere the gradually merges out into space. The water cycle does not occur within this region.
Answer: -
Organic compounds consisting of only carbon atoms and hydrogen atoms are known as hydrocarbons.
Hydrocarbons are used by us for mainly as a source of energy. Hydrocarbons make up gasoline which is used as fuel in automobiles.
Hydrocarbons depending on the type of unsaturation can be of three types - alkanes, alkenes and alkynes.
The properties of compounds are different, and in some cases very different, from those of the elements that compose them. This is because elements combine in compounds to become completely different substances with unique properties.
Compounds contain atoms of different elements chemically bonded in fixed ratios. An element is a pure chemical substance made up of atoms of the same kind. Compounds contain different elements in fixed ratios, arranged in a defined way by chemical bonds.
This is caused by different base properties where each element has a different number. Due to the number of electrons and differences in shell and valence electrons, different elements bond differently to certain other elements.
Compounds:
is composed of atoms of two or more different elements bonded together, and
can be broken down into simpler types of matter (elements) by chemical (rather than physical) means. from its components, and.
always contains the same proportions of atomic components.
Learn more about elements combine here;
brainly.com/question/6258301
#SPJ4
