CM8001

a. Exothermic process. Heat is released as it feels hot when one stands near it.

b. Endothermic process. Water absorbs heat from body to evaporate from the skin.

c. Endothermic process. Ice absorbs heat energy from the environment to break the intermolecular bonds in order for it to melt.

Explosion happens when the reactant being a solid turns into gas as the product through a reaction. This gas produced cause a sudden increase in volume which in turn becomes an explosion.
In order for there to be a good explosion, the product must have relatively low energy so that it is more stable than the reactant. Therefore, the reactant will have to have relatively weak bond strength as compared to the product.

Temperature is a quantitative measurement of heat present in the surroundings while heat is a form of internal energy that is felt by oneself.
An example is when you feel that the air is hot, which is the amount of heat present, but the temperature is not very high.

a. Gasoline has 98% isooctane and 2% heptane.

b. Octane rating is the ratio for the comparison with a standard for the fuel but there is no part in the ratio that refers to oxygenates. If one wants to know if the fuel contains oxygenates, more analysis has to be done or to contact the supplier about it.