How much heat is necessary to supply 2 kilograms of aluminum to raise its temperature by 20 ° C?
Answer:
36000J
Explanation:
Given parameters:
Mass of aluminum = 2kg = 2000g
Temperature rise = 20°C
Unknown:
Amount of heat needed for the temperature change = ?
Solution:
The amount of heat needed to cause this temperature rise is given as;
H = m c (T₂ - T₁)
H is the amount of heat
m is the mass
c is the specific heat of aluminum = 0.9J/g°C
Insert the parameters and solve;
H = 2000 x 0.9 x 20 = 36000J
The Zeroth Law of Thermodynamics<span> states that if two bodies are each in thermal equilibrium with some third body, then they are also in equilibrium with each other. Credit: Tim Sharp</span>
Answer:
-145.2kJ
Explanation:
Enthalpy is an extensive property as its value depends on the amount of substance present in the system.
If the enthalpy for one mole of methanol = -726 kJ/mol;
The Enthalpy for 0.2 mol is given as;
Enthalpy = 0.200 * 726
Enthalpy = -145.2kJ
It would take -145.2kJ for 0.200 mol of methanol to undego the combustion reaction.
It is due to a lack of providable energy to the next trophic level of the energy pyramid. Primary consumers only obtain around 10% of energy that producers have, and the energy depletes as you move further and further up the food chain, until you reach the tertiary consumers which have the least amount of energy at their disposal, meaning there are less of them than other organisms further down the energy pyramid.
Hope this helped!
