Studied by 22 peoplewhat are the properties of matter determined by?
chemical and physical properties of atoms and molecules
atom
submicroscopic particles matter which are building blocks for elements and molecules
molecule
2 or more atoms combine to make them. it can be made of the same element or different elements
chemistry
the science that seeks to understand the behavior of matter by studying the behavior of atoms and molecules (the study of matter)
strong bonds
make an object harder to break
what does it mean that science is empirical ?
it is based on obsesrvations and experiments
scientific law
A general hypothesis or statement about the relationship of natural quantities that has been tested over and over again and has not been contradicted
fact
A phenomenon about which competent observers can agree.
hypothesis
prediction
principle of falsifiability
for a hypothesis to be considered scientific, it must be testable and capable of being wrong
does data prove a hypothesis
no, it only supports a hypothesis
theory
unifying explaination of a scientific phenomena
matter
anything that has mass and takes up space, consisting of atoms and molecules in motion
the 3 states of matter
solid, liquid, gas
to measure the volume of a solid, use…
water displacement
structure of a solid
fixed volume and shape (tightly packed bonds
structure of a liquid
no shape but fixed volume (loose bonds)
structure of a gas
no shape or volume (very very weak bonds)
2 categories of matter
pure substances and mixtures
2 types of misxtures
heterogenous (layered boundaries like wet sand) and homogenous (no clear separation of the compounds)
element
substance that can not be broken down into a simpler substance
compound
substance of 2 or more elements in fixed definite proportions
homogenous mixture
composition is the same throughout (ex: air, bronze, sweet tea)
heterogeneous mixture
varries in composition throughout sample (ex: granite countertop)
methods of separating mixtures
decanting, distillation, and filtration
physical changes
a substance doesnt change into a new substance (phase change, ex: ice to water to steam)
physical properties (list)
density, color intensity, particle size, melting/freezing point, boinling point, texture
chemical change
a reaction forms a new substance
base unit of length
meter
base unit of mass
gram
base unit of time
second
amount of a substance
mole
base unit of electric current
ampere
base unit of luminous intensity
candela
precision
agreement and closeness of repeatable values. you can be precise but not accurate in measurements.
accuracy
agreement and consensus of measured values to the actual value
uncertainty/confidence factor
degree of measure value differs
atom
smallest identifiable unit of an element
Gerd Binning and Heinrich Roher
discovered “tunneling” current that allowed them to scan the surface on an atomic scale
what did Binnig and Roher’s discovery lead to?
electron scanning tunneling microscopy
law of conservation of mass
in a chemical reaction matter is neither created or destroyed
law of definite proportions
for a given compound the elements always combine in the same proportion
Law of multiple proportions
2 elements A and B can form different compounds by combining in different proportions and the ratio of these two is itself a small whole numebr
dalton’s atomic theory
-each element is composed of tiny indestructible particles called atoms
-all atoms of a given element have the same mass and other properties that distinguish them from the atoms of other elements
-atoms combine in simple whole number ratios to form compounds
-atoms of one element cannot change into atoms of another element. in chemical reaction atoms change the way that they are bound together with other atoms to form a new substance.
jj Thomson
did cathode ray experiment
RA millikan
did oil drop experiment showing that the particle had the same amount of charge as the hydrogen ion as thomson observed in his experiments
electron
negatively charged particle
neutrons
neutral particles
proton
positively charged particles
what is an atomic number?
number of protons
isotope
the same elements but with different mass due to varying number of neutrons.
ion
atoms or groups of atoms with a positive or negative charge
cation
when an atom loses an electron (positive charged ion)
anion
when an atom gains an electron (negative charged ion)
demitri Mendeleev
developed the modern periodic table
periodic law (2 points)
-when elements are arranged in order of increasing atomic mass, certain sets of properties recur periodically.
-elements having similar physical and chemical properties fall within a column
how are the elements arranged (left to right)?
in increasing atomic number.
what are rows of the periodic table called?
periods
what are the columns of the periodic table called?
families
areas of the periodic table
main group metals
transition metals
inner transition metals-(lanthanides and actinides)
metalloids
nonmetals
properties of metals
solid at room temp (except mercury)
reflective
conduct heat/electric current
malleable and ductile
lose electrons and form cations
metaloids
can exhibit properties of both metals and nonmetals
known as semiconductors (poor conductors of heat)
solid at room temperature
nonmetals
can be found in all three states of matter
poor conductors of heat or electricity
solids are brittle
gain electrons to become anions
except for H mostly found in the upper right on the periodic table
elements within a family have…
-similar chemical and physical properties
-the same number of electrons
what do metals tend to form?
cations
what do nonmetals tend to form?
anions
what do metaloids form?
tend to form cations but can also form anions
mole
quantity used in chemistry
charge of Zinc
2+
silver charge
1+
what is the charge of aluminum?
3+
compound
made of atoms held together by chemical bonds
bond
attraction force between atoms
ionic bonds
formed between a metal and a nonmetal where an electron transfers from one atom to another. the resulting cation and anion are attracted to each other by electrostatic forces. they are the strongest type of bond. ionically bonded elements are known as ionic compounds
covalent bonds
occur between nonmetal elements. this bond arises from the mutual attraction of 2 nuclei for the same electron (sharing) refered to as molecular compounds. balance between attractive and repulsive forces
chemical formula
represents the composition of the substance
molecular formula
lists the exact number and types of atoms of which the molecule is composed.
empirical formula
relative type and number of atoms in the compound (simplest ratio)
Atomic elements
they exist by themselves, all metals are atomic
molecular element
doesn’t exist by itself
what net charges does a ionic compound have
zero
naming ionic compounds (including alkali and alkaline earth metals)
metal followed by the nonmetal
nonmetal ending exchanged with “-ide”
type 2 metal and nonmetal ionic
metal then nonmetal
metal’s oxidation state is indicated by roman numerals between the two
hydrates
ionic compounds containing a specific number of waters for each formmula unit
name molecular compounds
name first nonmetal
change ending of second nonmetal to “-ide”
use prefixes on both unless the first one is one (no subscript
acids
release Hydrogen (H+) when disolved in water
sour taste and low pH value (less than 7)
can dissolve many metals
binary acids
have only 2 elements, H+ and a nonmetal
how to name oxyacids
h cation and polyatomicc anion that contain atoms
take bace of nonmetal and add “-ic acid”
is there a difference between atomic weight and atomic mass?
no. it is the mass of one mole of the element
combustion analysis
burning of a known mass of compound and weighing the product. generally used for organic compounds containing C, H, and O and can determine the original amount of constituent elements.
organic compound
mainly made of C, H, sometimes O, N, P and S with traces of other elements (main focus is carbon) bond almost exclusively covalently. when carbon bonds they form straight/branched chains or rings
charge of Sc
3+
phosphate
PO4 charge=3-
Acetate
C2H3O2 charge -1
hydroxide
OH charge -1
carbonate
CO3 charge -2
ammonium
NH4 charge 1+
sulfate
SO4 charge 2-
chromium type 2 metal
Cr 2+ or 3+
Iron type 2 metal
Fe 2+ or 3+
Note
Flashcard