CM8001

a. Exothermic. Process requires a larger amount of energy to form bonds than to break bonds. Energy of Products is lower than that of reactants.

b. Endothermic. Process requires a larger amount of energy to break bonds than to form bonds. Energy of products is larger than the energy of reactants.

c. Endothermic. Process requires a larger amount of energy to break bonds than to form bonds. Energy of products is larger than the energy of reactants.

In the reactants, the total bond strength should be lower than that of the products. This is because lesser energy is needed to break all the bonds in the reactant than the energy needed to form all the bonds in the products. In this way, only can the reaction be exothermic. Furthermore, the product needs to be a gas in order for the volume to expand drastically during the explosion.

Heat is a form of energy transfer – energy that flows from a hotter to cooler object. Heat is a consequence of motion at the molecular level, while temperature is a measure of the average speed of that motion. Heat is what we can feel with our senses, whereas temperature is a more specific measure of how hot object is.

For example, a pot of boiling water has a temperature of 100 degree celsius while ice has a temperature of 0 degree celsius. However, ice contains more energy or heat compared to a pot of boiling water.

a. It tells us that it has a knocking characteristic of 98% iso-octane and 2% of heptane.

b. Oxygenates are compounds that assist in the combustion in engines and help reduce co-emission and reduce knocking. The octane rating can be increased in the presence of oxygenates however the octane rating itself does not tell us whether the fuel contains oxygenates.