Given the following equation:
N2 + Cl2 > @ NCL3 H=+230 kJ
a) What mass of N2 would absorb 96.5 kJ of heat as it reacts?
b) What volume of Cl2 at STP would be required to react with the N2 in part (a)?
I do not know how to solve this problem. My mindset is that it involves stoichiometry in some way, I do not know how to manipulate it though.
Balance the equation.
N2 + 3Cl2 ==> 2NXl3 dH = 230 kJ
If 28g N2 absorbs 230 kJ, then how much N2 is needed to absorb only 96.5?
28 x (96.5/230) = ?
Convert g N2 from part a to mols. mol grams/molar mass = ?
Use the coefficients in the balanced equation to convert mols N2 to mols Cl2.
Then mols Cl2 x 22.4 L/mol = L Cl2 at STP
I got 11.8 for A
and 14.15 for B
I obtained 11.7 for A. You probably used 14.008 for N.
The only way I can get your answer to part B is to convert mols N2 as 11.8/14 but it should be 11.8/28 = mols N2 = 0.421.
Then 0.421 x (3 mols Cl2/1 mol N2) = mols Cl2.
mols Cl2 x 22.4 = about 28.3 L
AHH! I accidentally put 2 mols for N2 instead of 1 I see now
To solve this problem, you are correct that stoichiometry is involved. Stoichiometry is a branch of chemistry that deals with the quantitive relationships between reactants and products in chemical reactions.
Here's how you can approach this problem step by step:
a) What mass of N2 would absorb 96.5 kJ of heat as it reacts?
1. Start by writing and balancing the chemical equation:
N2 + Cl2 → NCl3
The equation indicates that one mole of N2 reacts with one mole of Cl2 to produce one mole of NCl3.
2. Determine the molar enthalpy change of the reaction:
From the given equation, it states that the enthalpy change (H) is +230 kJ. This means that the reaction is endothermic, as indicated by the positive sign.
3. Use the molar enthalpy change to calculate the amount of heat absorbed:
The molar enthalpy change tells you how much heat is released or absorbed when one mole of reactants is converted to products. In this case, +230 kJ of heat is absorbed by the reaction.
4. Determine the molar ratio between N2 and enthalpy change:
From the balanced equation, the molar ratio between N2 and the enthalpy change is 1:230 kJ.
5. Convert the given heat (96.5 kJ) to moles:
Use the molar ratio to convert the given heat to moles of N2.
(96.5 kJ) x (1 mol N2 / 230 kJ) = 0.42 moles
6. Calculate the mass of N2 using the molar mass:
Look up the molar mass of N2, which is approximately 28 g/mol.
(0.42 moles) x (28 g/mol) ≈ 11.76 g
Therefore, the mass of N2 that would absorb 96.5 kJ of heat as it reacts is approximately 11.76 g.
b) What volume of Cl2 at STP would be required to react with the N2 in part (a)?
To determine the volume of Cl2, we need to use the ideal gas law and consider the molar ratio between Cl2 and N2 in the balanced equation:
1. Find the moles of Cl2 using the molar ratio:
From the balanced equation, the molar ratio between Cl2 and N2 is 1:1.
Since we know that 0.42 moles of N2 is required, the same amount of moles of Cl2 is also needed.
2. Convert moles of Cl2 to volume at STP:
At standard temperature and pressure (STP), the volume of one mole of any gas is 22.4 liters.
Thus, the volume of Cl2 required is 0.42 moles * 22.4 L/mol ≈ 9.41 liters.
Therefore, approximately 9.41 liters of Cl2 at STP would be required to react with the N2 from part (a).