Consider this row in the periodic table of elements. as we move from left to right, across the row, the elements a) change from nonmetals to metals. b) change from metals to nonmetals. c) start as gases but end as solids. d) show a decrease in atomic mass number.

B) change from metals to nonmetals.

The answer is: B) change from metals to nonmetals.

For example, alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons (one electron, earth alkaline metals (right next to alkaline metals) have higher ionization energy than alkaline metals, because they have two valence electrons.

Nonmetals are far right in the main group and they have highest ionization energy, because they have many valence electrons.

Atomic number is the number of protons, which is characteristic of a chemical element. Atomic number increases from left to right in Periodic table.

explanation:

the largest database of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. the number of potential organic compounds has been estimated at 1060—an astronomically high number. the existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities. the simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. in addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. we use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. the familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. we can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. this leads to differences in geometries and in the hybridization of the carbon orbitals.

i just learnt this recently but i need to look through my notes again