periodic table core questions Flashcards
define atom
tiny particles
define molecule
a group of atoms bonded togther
what are substances made of only one type of atom called
elements
what are substances made of two or more types of atoms chemically bonded called
compounds
what is the word for an element that always exists as two atoms bonded together
diatomic
which elements exist diatomically
oxygen nitrogen hydrogen and all of group 7
define a period
rows in the periodic table of elements
define group
columns of the periodic table
which side of the periodic table contains metals
left (of the staircase)
which side of the periodic table contains non-metals
right (of the staircase)
where are alkali metals found in the periodic table
group 1
where are halogens found in the periodic table
group 7
give 4 properties of metals
high melting point
good thermal and electrical conductors
ductile
malleable
give 4 properties of non-metals
low melting point
poor thermal and electrical conductors
brittle
what is the name for the smaller number given for each element
atomic number
what is the name for the bigger number given to each element
mass number
name 6 alkali metals in order of reactivity
lithium sodium potassium rubidium caesium francium
when cut how do alkali metals first appear
shiny
what is formed when alkali metals react with water
alkaline metal hydroxide
what happen to the reactivity of the alkali metals as you move down the group
increases
how are elements arranged on the periodic table
in order of atomic number (lowest to highest)
what is the name for the elements in the middle of the periodic table the ae not in a group
transition metals
what did Mendeleev do when creating the modern
left gaps for future elements as some were predicted
how did Mendeleev justify leaving gaps in the tabel
he said new elements would be discovered that would fit in the gaps
why was Mendeleev’s table accepted
he predicted the properties of the future elements
name 5 halogens in order of reactivity
astatine iodine bromine chlorine fluorine
state 3 properties of halogens (group 7)
non-metal highly reactive diatomic
what happens to the reactivity as you move down the halogens
decreases
name 3 noble gases
helium neon argon
state 3 properties of noble gases
non-metal inert(don’t react) gases
what type of oxides are acidic
non-metal oxides
what type of oxides are alkaline
metal oxides