Lesson 3 Flashcards
All chemical reactions exhibits the two
fundamental laws:
the law of conservation of
mass
the law of conservation of energy.
It is defined as the capacity to do
work.
Energy
________, unlike matter, cannot be seen,
touched, smelled, or weighed but all of its
form are capable of doing work.
Energy
directed energy change resulting from
a process.
work
There are different forms of energy namely:
Kinetic energy
Thermal energy
Chemical energy, and
Potential energy
All forms of energy can be ________ from one form
to another, but can neither be _______ nor ___________.
transformed
created
destroyed
In this law, the total quantity of
energy in the universe is assumed constant.
law of conservation of energy
it is the transfer of thermal energy between two bodies
that are at different temperatures
heat
is the study of heat change in chemical
reactions.
thermochemistry
is the specific part of the universe that is of interest to us
system
are the rest of the universe outside the
system.
surroundings
Three types of system:
(a) Open, (b) Closed and (c) Isolated system.
system where it can exchange mass and
energy, usually in the form of heat with its
surroundings.
open system
what system
Example. Boiling soup in an open saucepan
on a stove.
open system
A system that allows the transfer of
energy (heat) but not mass.
closed system
what system?
Example. A pressure cooker on a stove with
its lid tightly closed and the whistle in position
closed system
A system that does not allow the
transfer of either mass or energy.
isolated systm
what system
Example. A thermos flask containing hot
water
isolated
Any energy lost from the system, or the
given reacting mixture, is gained by the
surroundings.
exothermic process