Exo / Endo
Is photosenthysis an Exothermic or an Endothermic reaction?
endothermic reaction
what is the formula to calculate ΔH of the reaction?
ΔH = bond energy (reactant) - bond energy (product)
What is photochemical reaction?
It is a chemical reaction that takes place using the light
mention all factor that affect rate of reaction
concentration, pressure, surface area, and catalyst
What is reversible reaction?
It is a reaction which is product formed can be reverse to form the original reactant
During an endothermic reaction in a beaker if we are part of the surroundings and touched the beaker, it would feel ...
cold
Calculate the entalphy change of this reaction
H2 + Cl2 → 2HCl
Use the bond energies in the table to calculate the energy change for this reaction.
Bond energy
H−H 436 kJ/mol
Cl−Cl 243 kJ/mol
H−Cl 432 kJ/mol
Entalphy change = 679 - 864
= -185 kJ/mol
what is the reaction in photosynthesis?
carbon dioxide + water + sunlight --> glucose + energy
Why does a catalyst increase the rate of reaction?
it reduces the activation energy of the reaction
What are the two factors to look for when determining if the reaction is at equilibrium?
Forward and reverse reaction rates are equal and concentration is constant
If the energy required to break the bonds is less than the energy given out by making new bonds the reaction is
exothermic reaction
Calculate the entalphy change of this reaction.
2HBr → H2 + Br2
Bond energy
H−Br 366 kJ/mol
H−H 436 kJ/mol
Br−Br 193 kJ/mol
Entalphy change
= 732 - 629
= +103 kJ/mol
what is the catalyst used in decomposition of hydrogen peroxide?
Manganese (IV) oxide
Why does a higher temperature increase the rate of a reaction?
it increases both the frequency and energy of particle collisions
An exothermic reaction is allowed to reach equilibrium. If the temperature decrease, the equilibrium will shift to ...
the right side (toward the product side)
Explain about the energy in the endothermic reaction
the energy absorbed in bond breaking is greater than the energy released in bond forming
Hydrogen reacts with oxygen to form water:
2 H2 + O2 → 2 H2O
Bond energy
H−H 436 kJ/mol
O=O 498 kJ/mol
O-H 464 kJ/mol
-486 kJ/mol
What is catalyst used in catalytic converter?
Platinum, Rhodium, and Palladium
Why don't all collisions between particles cause a reaction?
Because not all the particles collide with enough energy
For the reaction...
energy + N2(g) + O2(g) <−> 2NO(g)
If O2(g) is removed, the concentration of N2 will _______.
increase
Sato mixes a solution of baking soda and water. The initial temperature of the solution is 22⁰C. She adds 10mL of vinegar and takes the temperature again. The final temperature is 17⁰C.
a. What is the reaction?
b. Is ΔH negative or positive?
a. endothermic reaction
b. ΔH is positive
Calculate the entalphy change of this reaction.
C2H6 + Cl2 → C2H5Cl +HCl
Bond energy
C−H 413 kJ/mol
Cl−Cl 243 kJ/mol
C−Cl 346 kJ/mol
H−Cl 432 kJ/mol
energy change = -122 kJ/mol
Mention three reaction happened in the catalytic converter.
2NO --> N2 + O2
2CO + O2 --> 2CO2
CxHy + O2 --> CO2 + H2O
When surface area is decreased the rate of reaction.... why?
Decreases, because there are LESS possible sites for correct collisions
For the reaction...
SO2(g) + O2(g) <−> SO3(g)
If the concentration of SO2(g) is increased, the equilibrium of the reaction will ___________.
shift to the right