Q: What is the change of entropy for 3.0 kg of water when the 3.0 kg of water is changed to ice at 0 °C? (Lf = 3.34 x 105 J/kg)
Answer:
-3670.33 J/K
Explanation:
Entropy: This can be defined as the degree of randomness or disorderliness of a substance. The S.I unit of Entropy is J/K.
Mathematically, change of Entropy can be expressed as,
ΔS = ΔH/T ....................................... Equation 1
Where ΔS = Change of entropy, ΔH = heat change, T = temperature.
ΔH = -(Lf×m).................................... Equation 2
Note: ΔH is negative because heat is lost.
Where Lf = latent heat of ice = 3.34×10⁵ J/kg, m = 3.0 kg, m = mass of water = 3.0 kg
Substitute into equation
ΔH = -(3.34×10⁵×3.0)
ΔH = - 1002000 J.
But T = 0 °C = (0+273) K = 273 K.
Substitute into equation 1
ΔS = -1002000/273
ΔS = -3670.33 J/K
Note: The negative value of ΔS shows that the entropy of water decreases when it is changed to ice at 0 °C
Answer:
endothermic
Explanation:
the negative sign of the heat indicates that heat is being drawn into the system, thus endothermic
Answer:
I would sieve them because the flour will go through but not the rice
Explanation:
NaCI is the answer, in what my teacher taught me.
Hope I helped :)
Sublimation occurs more readily when definite weather circumstances are present such as low relative humidity and dry winds. Sublimation also occurs more at higher altitudes where the air pressure is less than at lower altitudes and energy such as strong sunlight is also needed. Sublimation happens a lot in the south face of Mt. Everest which have low temperatures, strong winds, intense sunlight, very low air pressure and the recipe for sublimation to occur.
