Answer:
A neutral particle made of an electron and hole
Explanation:
Exciton
It is the combination of an electron and a hole ( hole refers to the vacancy of an electron ) . And , as both the electron and the hole have the same charge but the polarity is opposite , the combination will lead to a neutral compound , i.e. , Exciton have no charge and so neutral .
It is free to move in the nonmetallic crystal and since it charge less , it is difficult to detect it directly .
Answer:
Earthquakes are measured using instruments called seismometers, that detect the vibrations caused by seismic waves as they travel through the crust. Also, laser beams can be used
Explanation:
Fluorine is the most electronegative element, while francium is one of the least electronegative.
Answer:
3.727x10^24 atoms.
Explanation:
When calculating how many molecules are in a compound or element, we refer to Avogardo's number.
Your equation will look like this: 1 mole/ 6.022x10^23 molecules (Avogardo's number).
Multiply 6.19 by Avogardo's number to get your answer.
Maybe u should choose D beacause it makes more sense.
