Answer:
1. Q = 8.66 KJ
2. Q = 7.58 Kcal
3. Q = 0.71 KJ
4. Q = 24.31 Kcal
Explanation:
1. The quantity of heat absorbed can be determined by:
Q = mcΔθ
where: Q is the quantity of heat absorbed or released, m is the mass of the substance, c is the specific heat capacity of water = 4.2 j/g and Δθ is the change in temperature.
= 45.2 × 4.2 × (76.9 - 31.3)
= 8656.704
∴ Q = 8.66 KJ
The quantity of heat absorbed is 8.66 KJ.
2. Q = mcΔθ + mL
Where L is the latent heat of fusion of ice = 334 J.
= m(cΔθ + L)
= 72.1(4.2 × 25.2 + 334)
Q = 31712.464 J
= 7579.466 calories
The total heat released is 7.58 Kcal.
3. Q = mcΔθ
= 55.5 × 0.129 × (123.4 - 24.6)
= 707.3586
The quantity of heat required to increase the temperature of gold is 0.71 KJ.
4. Q = mL
Where: L is the specific latent heat of vaporization = 533 calories.
Q = 45.6 × 533
= 24304.8
The quantity of heat required to change water to steam is 24.31 Kcal.
Answer:
22.5L
Explanation:
Given parameters:
Volume of N₂O₃ = 15liters
Unknown:
volume of oxygen gas = ?
Solution:
To solve this problem, we need to work from the known to unknown. The known is N₂O₃. We can find the number of moles from here.
Note: The condition is Standard temperature and pressure
Number of moles =
Number of moles of N₂O₃ = = 0.67moles
The equation of the reaction;
2N₂ + 3O₂ → 2N₂O₃
Since the equation is balanced;
2 moles of N₂O₃ is produced from 3 moles of O₂
0.67moles of N₂O₃ is produced from = 1.01 moles of O₂
Therefore;
Volume of O₂ = 1.01 x 22.4 = 22.5L
Answer:
The correct answer is B.2.52 mol
Explanation:
The molarity of a solution (M) expresses the number of moles of solute there is in 1 liter of solution. If we have the molarity (M) and the volume in liters (L), we simply multiply M x V to obtain the moles, as follows:
M = 2.21 = 2.21 moles/L
V = 1.14 L
M x V = 2.21 moles/L x 1.14 L = 2.5194 moles ≅ 2.52 moles
Based on the information given in the question, the cholesterol has:
a mass of 0.406 g
&
moles of 0.00105 mol
Now, Molecular Mass = Mass ÷ Moles
= 0.406g ÷ 0.00105mol
= 386.6667 g/mol
≈ 386.67 g/mol
The numbers inside the boxes represent the atomic number. the circles and dots represent the shells and electrons.