0.5 mg/mL would be expressed as 500 ug/uL
Answer: final temperatures will be
a) water 21 C
b) concrete 20.005 C
c) steel 20.008 C
d) mercury 53 C
Explanation:
Change in temp dT = dH / (mass x specific heat)
Specific heat of these materials can be found from many sources:
water = 1 kcal / kg C
concrete = 210 kcal / kg C
steel = 114 kcal / kg C
mercury = 0.03 kcal /kg C
So dT (water) from 1 kcal heat into 1 kg water = 1 kcal / (1 kg x 1 kcal/kg C) = 1 C therefore the final temperature is 20 + 1 = 21 C
But dT (steel) = 1 kcal / (1kg x 114 kcal/kg C) = 0.008 C so the final temperature is 20 + 0.008 = 20.008 C
The results for concrete and mercury are calculated in the same way
Answer:
Explanation:
The change in enthalpy of a substance when heated is given by
ΔH = m x Csp x ΔT
so the enthalpy change is dependent on the specific heat , i.e its capactity to absorb heat, and is not influenced by factors such as being closer to the melting point, volume , potential energy or being a solid or liquid.
By Pleistocene ice age is meant the glacial periods that appeared in the Pleistocene. The Pleistocene is the first epoch of the Quaternary. It is an epoch when there was a so called ''ice age'' on the Earth, or rather a glacial period. During this ice age the planet had much lower temperatures on a global scale. The climate was also much drier. Lot of ocean water was frozen in the ice sheets that were stretching deep into the North American and Eurasian continents, which resulted in much lower sea levels that today as well. The places further north than 40 degrees of latitude were almost exclusively covered with ice, so life was almost impossible apart from some coastline places.
