introduction Flashcards
What is the definition of matter?
anything that occupies space and has mass
Describe solid particles
locked in rigid positions and close together
describe liquid molecules
closed together but can move around
describe gas molecules
far apart and move randomly
what is a pure substance
a substance made of only one type of compound or element with a constant composition
what are the diatomic elements
H2, N2, O2, F2, Cl2, l2, Br2
what is the difference between homogeneous and heterogeneous
homo- division between substances is not visible
hetero- division between substances is visible
what is the difference between chemical and physical properties?
physical- observed without changing the substance
chemical- substance reacts to form a new substance
intensive v.s. extensive properties
intensive- independent from sample size
extensive- dependent from sample size
define kinetic and potential energy
kinetic- energy associated with motion
potential- energy stored in an object, such as in chemical bonds or a stretched spring.
mass
kilograms
length
meter
time
seconds
temperature
kelvin
amount of substance
mole
how is density calculated
d= m/v
rules to determine if a digit is significant
- all non-zero numbers are significant
- leading zeros are not significant
- zeros following significant digits are significant
how do you round numbers when the digit that is being dropped is exactly 5?
if the number being rounded is even, it stays the same.
if it’s odd, it rounds up.
what is dimensional analysis?
a method to check units when working on problem, helping to avoid errors and ensuring correct units.
