IN 4Ca(OH)2 how many atoms of calcium.

This substance contains 4 atoms. Ca = 1. O = 1. H = 2 because H2 means two atoms of the substance it comes after.

"hydrogen bonding is the attraction of h atoms in the water molecule (slight + charge) to o atoms in a neighboring water molecule (slight - charge); it is a weak interatomic force. but it is still strong enough to the water molecules "stick" together."

i don't see a text, but i am gonna assume this *orbit* the curved path, usually elliptical, described by a planet, satellite, spaceship, etc., around a celestial body, as the sun.