Answer:
See explaination
Explanation:
1. The addition of group 3A elements to group 4A semiconductors decreases the conductivity of the group 4A semiconductors: Wrong
The addition of 3A group elements inreases the conductivity and make them extrinsic semiconductors( p-type)
2. The conductivity of semiconductors can be increased by the doping process.: Correct
3.As the temperature increases, the conductivity of semiconductors decreases.. wrong
As the temperature increases, the conductivity of semiconductors increases.
4. The addition of group 5A elements to group 4A semiconductors increases the conductivity of the group 4A semiconductors: Correct : They will create n-type semicoductor.
5.Holes are charge carriers in p-type semiconductors: Correct
6. Electrons are charge carriers in n-type semiconductors: Correct
Answer:
0.196 M
Explanation:
First, we have to calculate the moles of sodium hydroxide.
moles = mass / molar mass
moles = 3.9280 g / (39.997 g/mol) = 0.098207 mol
It is important to realize that even though 300 mL is the volume of water firstly added to dissolve the hydroxide, the flask is then filled to the mark, meaning that the volume of the solution is 500 mL = 0.500 L.
The molar concentration of sodium hydroxide is:

The concentration is an intensive property, that is, it does not depend on the amount of matter. As a consequence, the concentration of the 50 mL of solution in the buret is the same as the concentration in the flask.
You did not specify the types, but I believe the answer would be gamma radiation.