Molecules in a sample of nh3(l) are held closely together by intermolecular forces
(1) existing between ions(2) existing between electrons(3) caused by different numbers of neutrons(4) caused by unequal charge distribution

Molecules in a sample of NH3(l) are held closely together by intermolecular forces existing between ions. The answer is number 1. NH3 is governed by hydrogen bonding. Hydrogen bonding is the bonding between an H atom and the element that it combines with.

a  solution  is always transparent, light passes through with no scattering from solute particles which are molecule in size. the  solution  is homogeneous and does not settle out. a colloid is intermediate between asolution  and a  suspension. while asuspension  will separate out a colloid will not.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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