Chemistry Flashcards
(31 cards)
1
Q
solid state properties:
A
- definite volume
- maintains shape regardless of container
- particles lie close together in regular pattern
2
Q
liquid state properties:
A
- definite volume
- assumes shape of container
- particles are close together but can move past one another
3
Q
gas state properties:
A
- no definite shape or volume, assumes of container
- particles are far apart and move around randomly
4
Q
physical properties:
A
- are observed/measured without changing composition of material
5
Q
chemical properties:
A
- determine how a substance can be converted into another substance
6
Q
all matter is EITHER
A
- pure substance or
- mixture
7
Q
pure substance:
A
- composed of single component
- constant composition
- cannot be broken down by physical change
- further classified as either: element or compound
8
Q
element
A
- pure substance that cannot be broken down by chemical change
9
Q
compound
A
- pure substance formed by chemically joining 2+ elements
10
Q
mixtures
A
- composed of more than 1 component
- varying composition
- can be separated into parts by physical process
- ex: sugar dissolved in water
11
Q
density formula
A
mass (g) / volume (mL)
12
Q
properties of metals:
A
- located on left side of periodic table
- good conductors of heat & electricity
- shiny solids @ room temp
*except for mercury (Hg) = liquid @ room temp
13
Q
properties of nonmetals:
A
- located on right side of periodic table
- dull appearance
- poor conductors of heat & electricity
- can be solid, liquid, or gas
14
Q
properties of metalloids:
A
- located on solid line
- intermediate properties between metals & nonmetals
- 7 metalloids = boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), and astatine (At)
15
Q
major minerals
A
at least 100mg needed in daily diet
16
Q
trace elements
A
<15mg needed in daily diet
17
Q
3 subatomic particles that all atoms are made of:
A
- protons
- neutrons
- electrons
18
Q
properties of the nucleus
A
- location of protons and neutrons
- dense core of atom
- location of most the atom’s mass
19
Q
properties of the electron cloud
A
- location of electrons
- comprises most of the atom’s volume
- mostly empty space
20
Q
atomic number
A
- # above element symbol
- equal to # of protons = # of electrons (in neutral atoms)
21
Q
isotopes
A
atoms of the same element that have different number of neutrons
22
Q
atomic weight
A
- number below element symbol
- measured in atomic mass units
- this weight is the average of the masses of the naturally occurring isotopes
23
Q
electron structure
A
- principal energy levels (shells)
- electrons in lower # shells = closer to nucleus
- shells are divided into subshells (s,p,d,f)
24
Q
subshells consist of:
A
- orbitals = region of space where the probability of finding an electron is high
- each orbital can hold 2 electrons
25
covalent bonds:
- sharing of electrons
- bond between 2 nonmetals OR metalloid and nonmetal
26
ionic bonds:
- transfer of electrons from one element to another
- bond between a metal & nonmetal
- consist of oppositley charged ions that have strong attraction to each other
- forms either a cation or anion
27
cations:
- positively charged ions
- has fewer electrons than protons
- by losing 1-3 electrons, at atom forms a cation with a filler outer shell of electrons
28
anions:
- negatively charged ions
- more electrons than protons
- by gaining 1-3 electrons, atoms form anion with filler outer shell of electrons
29
octet rule:
- main group elements are most stable when they posses an octet of electrons in its outer shell (8)
30
metals always form ___ and nonmetals always form ___
- cations
- anions
31
physical properties of ionic compounds:
- crystalline solids
- high melting & boiling points
- when dissolved in water, they separate into cations & anions
