Answer:
3.11 mol/kg
Explanation:
Molality M = number of moles of solute, n/mass of solvent, m
To calculate the number of moles of glycerol (C₃H₈O₃) in 22.75 g of glycerol, we find its molar (molecular) mass, M',
So, M' = 3 × atomic mass of carbon + 8 × atomic mass hydrogen + 3 × atomic mass of oxygen
= 3 × 12 g/mol + 8 × 1 g/mol + 3 × 16 g/mol = 36 g/mol + 8 g/mol + 48 g/mol = 92 g/mol.
So, number of moles of glycerol, n = m'/M' where m' = mass of glycerol = 22.75 g and M' = molecular mass of glycerol = 92 g/mol
So, n = m'/M'
n = 22.75 g/92 g/mol
n = 0.247 mol
So, the molality of the solution M = n/m
Since m = mass of ethanol = 79.6 g = 0.0796 kg, substituting the value of n into the equation, we have
M = 0.247 mol/0.0796 kg
M = 3.11 mol/kg
So, the molality of the solution is 3.11 mol/kg.
Answer:
6.52 × 10^14 Hz
i don't know if that's right tbh
The expected final temperature of the block, given that 586 J of heat were added to it is 55.5 °C
<h3>How to determine the final temeprature</h3>
We'll begin by obtaining the change in the temperature of the block. This can be obtained as follow:
- Specific heat capacity of block (C) = 0.240 J/gºC
- Heat added (Q) = 586 J
- Mass of block (M) = 80.0 g
- Change in temperature (ΔT) =?
Q = MCΔT
Divide both sides by MC
ΔT = Q / MC
ΔT = 586 / (80.0 × 0.240)
ΔT = 586 / 19.2
ΔT = 30.5 °C
Finally, we shall determine the final temperature of the block. This can be obtained as follow:
- Initial temperature (T₁) = 25 °C
- Change in temperature (ΔT) = 30.5 °C
- Final temperature (T₂) = ?
ΔT = T₂ – T₁
30.5 = T₂ – 25
Collect like terms
T₂ = 30.5 + 25
T₂ = 55.5 °C
Thus, from the calculation made above, we can conclude that the final temperature is 55.5 °C
Learn more about heat transfer:
brainly.com/question/14383794
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Hey there : !
density = 10.5 g/cm³
volume = 23.6 cm³
therefore:
D = m / V
10.5 = m / 23.6
m = 10.5 * 23.6
m = 247.8 g
hope this helps!
The answer above is correct:)
