Plz help Why is magnetism an example of a non-contact force?
O Magnetic fields can push or pull objects without touching the objects.
O Magnets can hold materials in place.
Magnetic fields are created by moving electrons.
Electrical fields can be attractive or repulsive.

As changes in energy levels of electrons increase, the frequencies of atomic line spectra they emit

Nitric acid can be formed in two steps from the atmospheric gases nitrogen and oxygen, plus hydrogen prepared by reforming natural gas. in the first step, nitrogen and hydrogen react to form ammonia: (g) (g) (g) in the second step, ammonia and oxygen react to form nitric acid and water: (g) (g) (g) (g) calculate the net change in enthalpy for the formation of one mole of nitric acid from nitrogen, hydrogen and oxygen from these reactions. round your answer to the nearest .

An atomic nucleus is composed ofa)protons. b)protons and neutrons. c)protons and electrons. d)protons, neutrons, and electrons.