It takes 79.91 cal to vaporize 2.0 grams of an unknown substance. What is the enthalpy of vaporization for this substance.
The enthalpy is calculated as J/mol or kJ/mol, or even cal/mol, kcal/mol. We have mass here, and as this is an unknown sustance, then, we cannot know the molecular weight, so we will report the enthalpy as cal/g, kcal/g and kJ/g
dH = q/n = q/m
dH = 79.91 cal / 2 = 39.955 cal/g or 0.03955 kcal/g
converting this into Joules:
39.955 * 4.184 = 167,17 J/g or 0.16717 kJ/g
Hope this helps
It takes 79.91 cal to vaporize 2.0 grams of an unknown substance. What is the enthalpy...
For substance A, the entropy of the solid at 98.36 K is 7.36 Cal/molK, at this temperature it takes place the transition from one solid form to another, the transition heat is 284.3 cal/mol. The increase in entropy of the second solid modification is 98.36 K to 158.91 K and is 5.05 Cal/molK; The temperature of 158.91 K is the melting temperature of the solid. The melting heat of the solid is 476 cal/mol. From the melting point to the...
For substance A, the entropy of the solid at 98.36 K is 7.36 Cal/molK, at this temperature it takes place the transition from one solid form to another, the transition heat is 284.3 cal/mol. The increase in entropy of the second solid modification is 98.36 K to 158.91 K and is 5.05 Cal/molK; The temperature of 158.91 K is the melting temperature of the solid. The melting heat of the solid is 476 cal/mol. From the melting point to the...
For substance A, the entropy of the solid at 98.36 K is 7.36 Cal/molK, at this temperature it takes place the transition from one solid form to another, the transition heat is 284.3 cal/mol. The increase in entropy of the second solid modification is 98.36 K to 158.91 K and is 5.05 Cal/molK; The temperature of 158.91 K is the melting temperature of the solid. The melting heat of the solid is 476 cal/mol. From the melting point to the...
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