2nd test Flashcards
Matter
anything that has mass and occupies space
states
solid, liquid, gas
solid
constant volume and shape
liquid
constant volume but takes shape of container
gas
variable volume and shape that fills container
Chemical change (reaction)
change of one material into another with new properties (digestion, burning, rotting)
Physical change (appearance)
affect the form of a material but its not composition (melting ice, folding paper)
Mixtures can be…
heterogeneous, homogeneous
heterogeneous
two or more items that can be easily separated (trail mix)
homogeneous
two or more items that appear the same throughout
purse substances
constant composition (elements,compounds)
elements
a pure susbtance amde of only 1 atom. CHONPS and others (diatomic,isotopes,trace)
trace
elements the body needs in small amounts for homeostasis
isotopes
elements with same # of p+ and e-, but different # of neutrons
diatomic
always found paired in nature H2,N2, O2, F2, Cl2, Br2, I2
Ionic bonds
formed by transfer of valence electrons to form (cations, anions)
covalent bonds
formed by a sharing of valence electrons, two elements paired together (ploar, non polar)
cations
positive
anions
negative
polar bonds
when sharing is not equal
non-polar bonds
when sharing is equal
hydrophilic
loves water and polar bond
hydrophobic
dislike water and non-polar
elements
CHONPS and others (diatomic, isotopes, trace)
CHONPS
Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorous, Sulfur
compounds
elements paired together
Why are molecules shaped the way they are?
The function or job of a molecule will determine its shape (red blood cell has donut shape for oxygen & carbon dioxide)
All elements in the first column…
are known as alkali metals
