Answer:
Semiconductors are poor conductors at low temperatures, but their resistance decreases with increasing temperature.
Explanation:
A semiconductor can be defined as a crystalline solid substance that has its conductivity lying between that of a metal and an insulator, due to the effects of temperature or an addition of an impurity. Semiconductors are classified into two main categories;
1. Extrinsic semiconductor.
2. Intrinsic semiconductor.
The statement which best describes the electrical conductivity of metals and semiconductors is that semiconductors are poor conductors at low temperatures, but their resistance decreases with increasing temperature.
This ultimately implies that, semiconductors are typically an insulator (poor conductor) at low temperatures and a good conductor at high temperatures.
Additionally, conduction involves the transfer of electric charge or thermal energy due to the movement of particles. When the conduction relates to electric charge, it is known as electrical conduction while when it relates to thermal energy, it is known as heat conduction.
Answer:
Radio, Microwave, Infared, Ultraviolet
Explanation:
look at the EM spectrum
Answer:
C.KEEPS YOU FROM ILLNESS
Explanation:
THE WORD IMMUNE MEANS TO PROTECT THUS THE IMMUNE SYSTEM IS TO PROTECT YOUR BODY AGAINST PATHOGENS AND DEASISES CAUSING GERMS....
Answer:
a) C6H5COOH + H2O ↔ H3O+ + C6H5COO-
b) [ H3O+ ] = 2.517 E-3 M
c) pH = 2.599
Explanation:
a) balanced equation:
C6H5COOH + H2O ↔ H3O+ + C6H5COO-
⇒ Ka = ( [ H3O+ ] * [ C6H5COO- ] ) / [ C6H5COOH ] = 6.5 E-5
mass balance:
0.10 m = [ C6H5COO- ] + [ C6H5COOH ].....(1)
charge balance:
[ H3O+ ] = [ C6H5COO- ] + [ OH- ] .......[ OH- ] : comes from water, it's not significant
⇒ [ H3O+ ] = [ C6H5COO- ] .........(2)
b) (2) in (1):
⇒ 0.10 M = [ H3O+ ] + [ C6H5COOH ]
⇒ [ C6H5COOH ] = 0.10 - [ H3O+ ]
⇒ Ka = [ H3O+ ]² / ( 0.1 - [ H3O+ ] ) = 6.5 E-5
⇒ [ H3O+ ]² + 6.5 E-5 [ H3O+ ] - 6.5 E-6 = 0
⇒ [ H3O+ ] = 2.517 E-3 M
c) pH = - log [ H3O+ ]
⇒ pH = - Log ( 2.517 E-3 )
⇒ pH = 2.599
W = F = mg
(2)(9.8)
W = 19.6 N
