Answer:
Explanation:
In a conductor, electric current can flow freely, in an insulator it cannot.
Metals such as copper typify conductors, while most non-metallic solids are said to be good insulators, having extremely high resistance to the flow of charge through them.
Most atoms hold on to their electrons tightly and are insulators.
Answer:
1) D
2) A
Explanation:
1) Each group has the same number of valence electrons, which are the outer electrons.
2) Ionic bonds are between a metal and non - metal, the metal being sodium and the non - metal being chlorine.
Hydroelectricity is the best answer.
This is an article by the EIA, but the pie graph is the most helpful: https://www.eia.gov/energyexplained/?page=us_energy_home
Heat, like sound, is kinetic energy. Molecules at higher temperatures heave more energy, thus they can vibrate faster. Since the molecules vibrate faster, sound waves can travel more quickly.
So the answer is A.
