When sunlight hits the moon's surface, the temperature can reach 260 degrees Fahrenheit (127 degrees Celsius). When the sun goes down, temperatures can dip to minus 280 F (minus 173 C).
Answer:C
Explanation:
A process is called spontaneous if the process takes place on its own without the intervention of external factors.
The spontaneous processes are generally quick with observable rates of reaction.But processes can be spontaneous even with negligible rates of reaction.
Spontaneity of reactions depend on temperature.
This is because spontaneity is measured by gibbs energy or enthalpy.
Both of these measures are dependent on temperature.
So,temperature affects spontaneity.
The half life of uranium- 238 is
4.46 x10^9 years
Explanation
Half life is the time taken for the radioactivity of a isotope to fall to half its original value.
The original mass of uranium-238 is 4.0 mg
Half of original mass of uranium = 4.0 mg /2 = 2.0 mg
since it take 4.46 x 10^ 9 years for the sample to half the half life of uranium -238 = 4.46 x10^9 years
