Answer:
The activation energy for an endothermic reaction is quite large and usually takes extra energy from the environment, it is normally not a natural spontaneous process.
Explanation:
- Endothermic reactions require absorbing energy of the surrounding mainly in the form of heat.
- Chemical energy needs energy input to break the bonds.
- Examples of endothermic reactions: Photosynthesis
, melting of ice
, and evaporating liquid water.
Answer:
not sure about 6 but 7 should be c
Explanation:
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Answer:
If we have one mole of water, then we know that it will have a mass of 2 grams (for 2 moles of H atoms) + 16 grams (for one mole O atom) = 18 grams.
Explanation:
They are called guard rails
Answer: The mass of ice you would need to add to bring the equilibrium temperature of the system to 300 K is
kg.
Explanation:
We know that relation between heat energy and specific heat is as follows.
q = 
As density of water is 1 kg/L and volume is given as 400,000 L. Therefore, mass of water is as follows.
Mass of water = Volume × Density
= 
= 400,000 kg
or, =
g (as 1 kg = 1000 g)
Specific heat of water is 4.2 J/gm K. Therefore, change in temperature is as follows.
= 305 K - 273 K
= 32 K
Now, putting the given values into the above formula and calculate the heat energy as follows.
q =
= 
=
J
or, =
kJ
According to the enthalpy of melting of ice 333 kJ/Kg of energy absorbed by by 1 kg of ice. Hence, mass required to absorb energy of
kJ is calculated as follows.
Mass = 
=
kg
Thus, we can conclude that the mass of ice you would need to add to bring the equilibrium temperature of the system to 300 K is
kg.