Chapter 1 Flashcards
element
fundamental substance that can’t be chemically changed or broken down into anything simpler (there are 118)
hydrogen
75% of the observed mass in the universe
oxygen and silicon
together account for 75% of the earth’s crust
oxygen, carbon, and hydrogen
more than 90% of the human body
periods
the 7 horizontal rows
groups
the 18 vertical columns (contain elements with similar chemical properties)
main group elements
carbon, oxygen, hydrogen, nitrogen, and phosphorous
transition metal groups (examples)
labeled B –> in the middle of the table (ex. iron, copper, zinc, and gold)
inner transition metal groups
the 14 groups on the bottom of the table
property (seven examples)
any characteristic that can be used to describe of identify matter
- volume
- amount
- odor
- temperature
- melting pint
- solubility
- chemical behavior
Intensive properties (two/three examples)
have values that don’t depend on the amount of sample
- temperature (ex. ice cubes and icebergs have the same melting point)
- melting point
Extensive properties (two examples)
have values that do depend on the sample size
- length
- volume
physical properties (8 examples)
characteristics that don’t involve a change in a sample’s chemical makeup
- temperature
- color
- melting point
- electrical conductivity
- amount
- odor
- solubility
- hardness
chemical properties
characteristics that do involve a change in a sample’s chemical makeup
- rusting (of iron)
- combustion (of gasoline)
- tarnishing (of silver)
- hardening (of cement)
group 1A
Alkali Metals –> react rapidly and violently to water (forming products that are highly alkaline)
group 2A
Alkaline Earth metals –> less reactive than 1A (never found in nature in their pure state)
group 7A
Halogens –> colorful and corrosive metals
group 8A
Noble gases
metals (four identifiable features)
- largest category of elements (left side of the table)
- identifiable appearance (silver shine, solid at room temperature (except mercury), malleable, conductors of heat and electricity)
nonmetals
right side of periodic table (except hydrogen)
- 11 Gases
-1 liquid (Bromine)
- 5 solids at room temperature
Semimetals
semi because they are brittle and poor conductors (ex. silicon because its conductivity is somewhere between a metal and insulator)
Rober Boyle
credited for being the first to study chemistry as a separate intellectual discipline
chemical compounds
substances made of the atoms of multiple elements