Answer:
0.693kg of CuFeS2 is needed to produce 240 grams of Cu.
Explanation:
In 1 mole of CuFeS2 is associated 1 mole of Cu.
Molar mass of CuFeS2 = 183.5 g/mol
Molar mass of Cu = 63.5g/mol
No of moles of copper present in 240g of chalcopyrite = 240/63.5 = 3.779moles
we know
1 mole of Cu → 1 mole of CuFeS2
in 3.779 moles of Cu → 3.779 moles of CuFeS2
3.779 moles of CuFeS2 = 3.779 * 183.5 = 693.45grams
CuFeS2 in kg = 0.693kg
Well all reactions need energy to start it. The light is the energy that the reaction requires to start it. Sunlight also has no mass in the first place so laws of conservation of mass don't apply to it.
HI
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Answer:
Q = 1379.4 J
Explanation:
Given data:
Mass of water = 22 g
Initial temperature = 18°C
Final temperature = 33°C
Heat absorbed = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Specific heat capacity of water is 4.18 J/g.
°C
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 33°C - 18 °C
ΔT = 15°C
Q = 522 g ×4.18 J/g.°C× 15°C
Q = 1379.4 J
