Theoretical basics of Inorganic chemistry

Q1. What is rate of a reaction?

Answer: The rate in which a certain reaction takes place in. The rate of reaction can be changed by: using catalysts, increasing the surface area, using a larger quantity, apllying more heat.

 

Q2. How does temperature affect rate of reaction?

Answer: The higher temperature will cause the particles to move faster and to increase the number and strength of the collisions. So, a lower temperature will slow the speed at which the particles move and decrease the number and strength of the collisions. To add to the answer above, higher temperature gives off more energy (kinetic) to the particles. More energy allows the particle to collide with other particles with more energy. And they will collide much faster, which will eventually break the bond between them.

 

Q3. What is rate constant?

Answer: A constant rate of change is a object, number, percentage, graph etc. that goes either up down or sideways at a constant rate. For example, every hour a fire burns it uses 10 logs. so if it burned 2 hours it would use 20 logs. 3 hours it would use 30 logs. That is a constant rate of change. Something that wouldn't be a constant rate would be for example, if you sharpened your pencil after writing 150 words, then sharpened it again after writing 210 words the again after 87 words then again after 205 words, that would not be a constant rate. It has to constantly go up by thesame number. What is molecularity of a reaction?

 

Q4. What is the Effect of pH on rate of reaction?

Answer: It depends on which chemical reaction you are referring to. There are many factors that may affect reactions. The pH value may not affect it at all or it may need to be high or low.

 

Q5. Catalysts increase the rate of a reaction by?

Answer: Catalysts are very effective and economical in industrial area. Catalysts increase the rate of a reaction by reducing the activation energy of the reaction. activation energy is the overall energy needed for a reaction to initiate. Both reactions such as exothermic or endothermic has activation energy, so we need to overcome the activation energy for the reaction to proceed. Actually the way it works is quiet simple, it absorbs the reactant particles on its surface reducing their bond energy. When the energy between bonds is weaker, its easier for reactant particle to change to products. Activation energy comes from when reactant particles collide with each other with high kinetic energy.

 

Q6. What does it mean to describe a reaction as “reversible”?

Answer: A reversible reaction is a reaction where the reactants form products, which react together to give the reactants back.

 

Q7. Difference between rate and rate constant?

Answer: 1) rate constant varies with temperature while rate varies with temperature and Concentrations of reactants.... 2) unit of rate constant depends on the order of reaction while the unit of rate of reaction is always (mol/dm3)*1/sec

 

Q8. What is relative rate constant?

Answer: A relative rate constant the rate at which a reaction will take place. Ex. V = k [A][B] the constant ,k, is a constant value for the rate of the reaction in said equation.

 

Q9. Does enthalpy of reaction affect the rate of a reaction?

Answer: The enthalphy of a reaction does not influence the rate of reaction, it may however influence the rate of the reverse reaction, as we now would have a change in potential energy (for example an exothermic reaction requires more energy to go in the reverse then does an endothermic). This is why you can consider some products thermodynamically favourable - as they are the exothermic product which would require more energy to turn back towards reactants then to stay as products. Overall rate is not seen in the various rate law or rate of reaction equations utilised such as arrhenius temperature dependance or the rate law equation. Rate is indepedant of enthalpy WRT to forward reaction.

 

Q10. How is the rate constant related to concentration of reactants?

Answer: As a chemical reaction proceed the concentration of the reactantskeep on decreasing while those of the products keep on increasinghow ever the rate of the reaction is also found to decrease thisshow that the rate of the reaction is directly related to theconcentration of reactants.