Answer:
2.853881279 years
Explanation:
I multiplied 365 times 24 to get 8760 hours in a year. I then multiplied this by 60 to get 525600 seconds per year. Lastly, I divided 1500000 by 525600 in order to get the answer. Hope this helps!
Answer:
16.5 g
Explanation:
When a nonvolatile compound is dissolved in a pure solvent, the freezing point of the solvent is reduced, because the interaction solvent-solute requires more energy to be joined, and so, it freezes. This property is called cryoscopy, and the temperature change (ΔT) can be calculated by:
ΔT = Kc*W*i
Where Kc is the cryoscopy constant of the solute X, W is the molality of the solution, and i is the van't Hoff factor, which determines the percent of the solute that is dissolved. For organic molecules, such as alanine, i = 1.
The molality is the number of moles of the solute divided by the mass (in kg) of the solvent (1200 g = 1.2 kg). The molar mass of alanine is 89.09 g/mol, and the number of moles of it is the mass divided by the molar mass:
n = 45.8/89.09
n = 0.5141 mol
W = 0.5141/1.2 = 0.4284 mol/kg
So, Kc of X is:
4.10 = Kc*0.4284*1
Kc = 9.57 °C.kg/mol
So, if now sodium chloride is added to X, and the variation temperature is the same, and i = 1.82:
4.10 = 9.57*W*1.82
W = 0.2354 mol/kg
The number of moles of the solute is then:
W = n/1.2
0.2354 = n/1.2
n = 0.2825 mol
The molar mass of sodium chloride is 58.44 g/mol, thus the mass is the molar mass multiplied by the number of moles:
m = 58.44*0.2825
m = 16.5 g
<u>Answer:</u> The enthalpy of formation of HCN(g) is 135.1 kJ/mol
<u>Explanation:</u>
Enthalpy change is defined as the difference in enthalpies of all the product and the reactants each multiplied with their respective number of moles.
The equation used to calculate enthalpy change is of a reaction is:
For the given chemical reaction:
The equation for the enthalpy change of the above reaction is:
We are given:
Putting values in above equation, we get:
Hence, the enthalpy of formation of HCN(g) is 135.1 kJ/mol
Its important because the temp can either take away or add energy to a substance.
hope this helps
Is this a scienctif question cuss if so it not only helps u with math there’s a lot of subsists like history math English etc....