periodic table chemistry Flashcards
why is it called the periodic table?
because there are repeated patterns of properties
what does malleable mean?
easy to bend
what does ductile mean?
ability for metals to be drawn into wires
what does sonourous mean?
ringing sounds
what are metals helpful with?
good conductors of electricity
what state are metals in?
a solid state
what state are non-metals in?
a liquid or a gas
what is a melting point?
the temperature where a substance melts
do metals or non-metals have a higher boiling point?
metals have the higher melting point
do metals or non-metals have the lower melting point?
non-metals
who was john dalton?
he was the first person to propose atoms were small spherical balls
what did john dalton do
he arranged the elements in order of their masses
was Dalton right?
no his hypothesis was proved wrong
what did john Newland do?
he arranged the known elements in order of mass but he noticed that the properties of every eighth element seemed similar.
was john Newland right?
no he did not take into account that chemists were still discovering new ones
what year did john dalton propose his hypothesis?
1806
what year did john newland propose his hypothesis?
1864
what are groups?
vertical columns
where are metals on the pt
the left hand side
how does the line descend for metalloids
in a staircase
where are the non-metals
the right hand side
What do elements in the same group have in common.
they have similar boiling, melting point and density which are examples of similar properties.
what are periods?
horizontal rows
who was Dmitri Mendeleev
he was a Russian scientist
what did Dmitri do
he used patterns in the properties to create the very first periodic table
why did Dmitri leave gaps in his table
it was so when new elements were discovered they could put them into the table
What are the properties of metals
They are usually solid, shiny and malleable, ductile and sonorous, they also have a higher melting point
What are the properties of non-metals
They are dull, brittle and are not sonorous, they are also poor conductors of electricity and have low melting points and low densities as well
What does brittle mean
Brittle means easy to break
What is a metal-oid
A metal-oid is a semi-metal which has properties of both metals and non-metals
What are some metal-oids
Silicon, asaline and boron
in the periodic table do the atomic mass increase as you move across a period?
yes
what does strontium and nitrogen make?
it makes strontium nitrate
