Energy Produced by Reaction

In summary, "Energy Produced by Reaction" refers to the amount of energy released or absorbed during a chemical reaction. It is typically measured in joules (J) or kilojoules (kJ) using a calorimeter. The type of reactants, concentration, temperature, and presence of a catalyst can all affect the amount of energy produced by a reaction. Exothermic reactions release energy in the form of heat, resulting in a negative change in enthalpy (ΔH), while endothermic reactions absorb energy, resulting in a positive change in enthalpy (ΔH). Energy produced by reactions is used in everyday life in processes such as powering cars, cooking food, and generating electricity in power plants.
  • #1
Koyuki
7
0
the reaction of H and F produces about 500 kj/mol of energy:

how much energy is produced by the reaction of 2.0kg of H with 38 kg of F to produce 2 kmol of HF?

The answer is 5.0x 10 to the exponent 5 kJ... but I'm not sure why...

Please help! Thanks!
 
Physics news on Phys.org
  • #2
This is chemistry and should be in the chemistry forums, but try calculating the number of moles of each reactant. Remember Hydrogen and Florine are diatomic.
 
  • #3


I can explain the calculation for the energy produced by the reaction of 2.0 kg of H with 38 kg of F to produce 2 kmol of HF.

First, we need to convert the given masses of H and F to moles. We can use the molar mass of each element (1.008 g/mol for H and 18.998 g/mol for F) to calculate the number of moles present in 2.0 kg of H and 38 kg of F.

2.0 kg of H = (2,000 g)/(1.008 g/mol) = 1,984.13 mol
38 kg of F = (38,000 g)/(18.998 g/mol) = 2,000.05 mol

Next, we need to determine the limiting reactant in this reaction. Since 2 kmol of HF is produced, we know that 2 kmol of H is also consumed in the reaction. Therefore, H is the limiting reactant.

To calculate the amount of energy produced, we can use the given value of 500 kJ/mol for the energy produced by the reaction of H and F.

Energy produced = (500 kJ/mol) x (2,000 mol) = 1,000,000 kJ or 1.0 x 10^6 kJ

However, this value is for 2 kmol of HF. We need to calculate the energy produced for 2,000 mol of HF. This can be done by multiplying the energy produced by the molar ratio of HF to H, which is 1:1.

Energy produced for 2,000 mol of HF = (1.0 x 10^6 kJ) x (2,000 mol/2 mol) = 1.0 x 10^6 kJ x 1,000 = 1.0 x 10^9 kJ

Therefore, the energy produced by the reaction of 2.0 kg of H with 38 kg of F to produce 2 kmol of HF is 1.0 x 10^9 kJ or 1.0 GJ (gigajoules). I hope this helps clarify the calculation for you.
 

1. What is "Energy Produced by Reaction"?

"Energy Produced by Reaction" is the amount of energy released or absorbed during a chemical reaction.

2. How is energy produced by reaction measured?

Energy produced by reaction is typically measured in joules (J) or kilojoules (kJ) using a calorimeter.

3. What factors affect the amount of energy produced by a reaction?

The amount of energy produced by a reaction can be affected by the type of reactants, the concentration of reactants, temperature, and the presence of a catalyst.

4. What is the difference between exothermic and endothermic reactions in terms of energy produced?

In an exothermic reaction, energy is released in the form of heat, resulting in a negative change in enthalpy (ΔH). In contrast, an endothermic reaction absorbs energy, resulting in a positive change in enthalpy (ΔH).

5. How is energy produced by reactions used in everyday life?

Energy produced by reactions is used in many everyday processes, such as combustion engines in cars, cooking food, and powering electronic devices. It is also used in industrial processes, such as generating electricity in power plants.

Similar threads

  • Introductory Physics Homework Help
Replies
1
Views
621
  • Biology and Chemistry Homework Help
Replies
6
Views
1K
  • Introductory Physics Homework Help
Replies
8
Views
805
  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
732
  • Thermodynamics
Replies
4
Views
880
  • Introductory Physics Homework Help
Replies
4
Views
3K
  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
994
Back
Top