What would be the change in enthalpy if you detonated 10 grams of NI3?
2NI3 ==> N2 + 3I2
I looked up the enthalpy for this and found it to be -290 kJ/mol. Therefore, 10 g would be
-290 kJ x (10/2*molar mass NI3) = ?
To determine the change in enthalpy when detonating 10 grams of NI3 (nitrogen triiodide), you would need to know the enthalpy of formation of NI3 and the balanced chemical equation for the reaction.
Here are the steps to calculate the change in enthalpy:
1. Determine the balanced chemical equation for the detonation reaction of NI3. The balanced equation for the detonation of NI3 is:
2 NI3(s) → N2(g) + 3 I2(g)
2. Look up the molar mass of NI3. Nitrogen triiodide has a molar mass of 394.6 g/mol.
3. Calculate the number of moles in 10 grams of NI3. Divide the mass (in grams) by the molar mass to obtain the number of moles. In this case, the calculation is:
Moles of NI3 = 10 g / 394.6 g/mol
4. Determine the change in enthalpy using Hess's Law or enthalpy of formation data. Hess's Law states that the enthalpy change for an overall reaction is equal to the sum of the enthalpy changes for the individual steps. Alternatively, you can look up the enthalpy of formation (∆Hf) values for the compounds involved and use them to calculate the change in enthalpy. The change in enthalpy (∆H) can be calculated using the following equation:
∆H = ∑(∆Hf products) - ∑(∆Hf reactants)
5. Finally, substitute the ∆Hf values into the equation above, multiplying them by the stoichiometric coefficients from the balanced equation, and calculate the change in enthalpy.
Note: It is important to consult reliable reference sources, such as chemical databases or thermodynamic tables, to obtain the accurate and up-to-date enthalpy of formation values for the substances involved in the reaction.
By following these steps and performing the necessary calculations based on the specific enthalpy data, you can determine the change in enthalpy when detonating 10 grams of NI3.