Abond exists between a and b in the compound ab. a and b are sharing electrons. the type of bond is
*ionic
*metallic
*covalent
*neutral

Covalent

Explanation: A covalent bond is formed by sharing of electrons and usually present in non metals whereas ionic bond is formed by transfer of electrons and is formed by metals and non metals.

A metallic bond is present in metals which is formed due to the presence of valence electrons

A neutral bond is one which there is no formation of charges. Both covalent and ionic bonds result into formation of neutral compounds.

Thus A and B forms a covalent bond as there is sharing of electrons between them.

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.