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:
(slow)xy2+z→xy2z (fast) c step1:step2:xy2+z2→xy2z2
Explanation:
Step1: xy2+z2→xy2z2 (slow)
Step2: xy2z2→xy2z+z (fast)
2XY 2 + Z 2 → 2XY 2 Z
Rate= k[xy2][z2]
When the two elementary steps are summed up, the result is equivalent to the stoichiometric equation. Hence, this mechanism is acceptable. The order of both elementary steps is 2, which is ‘≤3’; this also makes this mechanism acceptable. Furthermore, the rate equation aligns with the experimentally determined rate equation, and this also makes this mechanism acceptable. Therefore, since all the three rules have been observed, this mechanism is possible.
Answer:
3.62 g/cm³
Explanation:
density = mass ÷ volume
Therefore, do 12.69 divided by 3.5
Answer:
Ka = 1.52 E-5
Explanation:
- CH3-(CH2)2-COOH ↔ CH3(CH2)2COO- + H3O+
⇒ Ka = [H3O+][CH3)CH2)2COO-] / [CH3(CH2)2COOH]
mass balance:
⇒<em> C</em> CH3(CH2)2COOH = [CH3(CH2)2COO-] + [CH3(CH2)2COOH] = 1.0 M
charge balance:
⇒ [H3O+] = [CH3(CH2)2COO-]
⇒ Ka = [H3O+]²/(1 - [H3O+])
∴ pH = 2.41 = - Log [H3O+]
⇒ [H3O+] = 3.89 E-3 M
⇒ Ka = (3.89 E-3)² / ( 1 - 3.89 E-3 )
⇒ Ka = 1.519 E-5
Answer:
Lithium hydroxide is a base.
Carbon dioxide is the anhydride of the carbonic acid, H₂CO₃.
Therefore, the reaction awaited is a typical neutralization reaction with the formation of a salt and water.
2LiOH + CO₂ → Li₂CO₃ + H₂O
So, 2*20 = 40 moles of LiOH react with 20 moles of CO₂.
Molar Mass of LiOH = 23.95 g/mol
So, 40 * 23.95 = 958 g
