PLEASE HELP PLEASE Octane (C8H18) is a component of gasoline that burns
according to the following equation:
C8H18(l) + 25/2 O2(g) →8 CO2(g) + 9 H2O(g)
ΔΗχη= -5074.1 kJ
What mass of octane (in g) is required to produce 4910kJ of heat?

Suppose you have designed a new thermometer called the x thermometer. on the x scale the boiling point of water is 129 ? x and the freezing point of water is 13 ? x. part a at what temperature are the readings on the fahrenheit and x thermometers the same?

If we compare and contrast electromagnetic waves with sound waves, all but one statement is true. that is a) sound waves require a medium to travel while electromagnetic waves do not. b) electromagnetic waves can travel through the vacuum of space while sound waves cannot. c) electromagnetic waves must have a medium in which to travel, but sound waves can travel anywhere. eliminate d) sound waves must bounce off of matter in order to travel while electromagnetic waves do not require matter to be present.

All forces cause motion? true or false