The answer is b.
Hope that helps :)
The correct option is B.
Stars live out most of their lives at MAIN SEQUENCE. Stars generally are divided into three major stages, these are:
1. Pro stars and pre-main sequence star
2. Main sequence and giant star
3. Variable stars
Major stages in the life of a star can last for millions of years.
Answer:
Zn =⇒ Zn+2(0.10) + 2e- (anode)
Zn+2(?M) + 2e- === Zn(s) (cathode)
Zn + Zn+2(?M) ===⇒ Zn+2(0.10) + Zn
E = E^o -0.0592 log Q; in this case E^o is zero.
E = - 0.0592 /n logQ where n is the number of electrons transferred, in this
case n = 2
23 mV x 1 volt/1000mv = 0.023 Volts
0.023 = -0.0592 / 2 log(0.10) / [Zn+2]
0.023 = -0.0296 { log 0.10 – log [Zn+2] }
0.023 = -0.0296{ -1 - log[Zn+2] }
0.023 = +0.0296 + 0.0296log[Zn+2]
-0.0066 = 0.0296log[Zn+2]
-0.22= log[Zn+2]
[Zn+2] = 10^-0.22 = 0.603 Molar
The reaction is extremely exothermic, producing a bright yellow light and a great deal of heat energy.
