CM8001

a) Exothermic. Heat released as it burns.

b) Endothermic. Water absorbs heat necessary for evaporation, skin feels cooler.

c) Endothermic. Ice absorbs heat necessary for melting.

The relative bond strength of the reactants must be stronger than that of the products.

Solid -> gas very rapidly, releasing energy quick and massive.

Heat: Energy flow from a hotter object to a colder object(motion).

Temperature: Determine the direction of heat flow, and the measure of the average speed of motion.

Example:
Heat.
1 ice on hand VS 5 ices on hand
More contact results in colder
Both case have the same temperature but more heat transferred from hand to 5 ices.

Temperature of hand is higher than ice. Therefore, heat transfers from hand to ice.

a) knocking characteristic of 98% isooctane and 2% of heptane.
– higher ability to burn smoothly without knocking
– more resistant to knocking

b) does not have enough information to know whether it contains oxygenates.