Answer:
1425 mmHg.
Explanation:
The following data were obtained from the question:
Initial volume (V1) = 1.5 L
Initial pressure (P1) = 1 atm
Final volume (V2) = 0.8 L
Final pressure (P2) =?
Next, we shall determine the final pressure of the gas by using the Boyle's law equation as follow:
P1V1 = P2V2
1 × 1.5 = P2 × 0.8
1.5 = P2 × 0.8
Divide both side by 0.8
P2 = 1.5/0.8
P2 = 1.875 atm
Finally, we shall convert 1.875 atm to mmHg.
This can be obtained as follow:
1 atm = 760 mmHg
Therefore,
1.875 atm = 1.875 × 760 = 1425 mmHg.
Therefore, the new pressure of the gas is 1425 mmHg.
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
The kinetic energy theory of matter states that all particles of matter are in constant motion.
Kinetics has to do with some kind of movement, which is why this answer is the only plausible one.
Answer:
5.79 × 10^23 Oxygen atoms
Explanation:
Number of Oxygen atom in the compound = 4×3 = 12
Molar mass of Al2(SO4)3 = 342 g/mol.
No of mole = mass/molar mass = 2.74/342 = 8.01×10^-03 mole
2.74g of Al2(SO4)3 × 1 mole of Al2 (SO4)3 / 342g of Al2 (SO4)3 * 12 mole of Oxygen/ 1mole of Al(SO4)3 * 6.02×10^23 Oxygen atom/ 1 mole of Oxygen
= 5.79×10^23 Oxygen atoms
