Chapter 2 Chem Flashcards
(18 cards)
Energy
capacity to do work; involved when there is a change in matter
Endothermic
energy is going in, energy is absorbed; ex: boiling water
Exothermic
energy is released; ex: freezing water
Law of Conservation of Energy
during any physical or chemical changes, the total quantity of energy in the system remains constant
Heat
energy transferred between objects that are at different temperatures
Temperature
the measure of how much kinetic energy moving particles have
Kelvin
0 is absolute zero
Celsius
0 is waterś freezing point
Theory
well-tested explanation
Law
a statement that explains behavior in the natural
Conclusion
an explanation for one experiment
Accuracy
how close measurement is to the accepted amount
Precision
how closely several measurements agree
Significant figures
all of the digits that are known and an uncertain digit
Rules for sig figs
- all non-zero numbers are significant
- exact numbers have an infinite number of sig figs
- conversion factors/ defined numbers have infinite sig figs
Rules for zeros
- zeros appearing between nonzero digits are significant
- zeros left of all nonzeros are not significant
- zeros right of a number and decimal are significant
- zeros at the end of a number but no decimal are not significant
rules for sig figs in addition and subtraction
round to the lowest number given from the decimal places
rules for sig figs in multiplication and division
round to the lowest number of sig figs that were given
