atoms Flashcards
what is the structure of an atom. draw a diagram
nucleus in the centre with the protons (positive charge) and neutrons (neutral charge) in the nuleus. electrons (negative charge) circles around the shells
symbol for potasium hydroxide
KOH
Na + H20 = NaOH + H2.
BALANCE
2Na + 2H20 = 2NaOH + H2
Na + Cl2 = NaCl. Which of these is the correct balanced equation?
You said: 2Na + Cl2 = 2NaCl
Which of these is the correct balanced equation for the reaction between potassium and bromine?
You said: 2K(s) + Br2(g) = 2KBr(s)
Which of these is the correct balanced equation for the reaction between potassium and water?
2K(s) + 2H20(l) = 2KOH(aq) + H2(g)
compared to most other metals, what properties do the alkali metals have?
You said: low melting points and low densities
When sodium hydroxide dissolves in water, what sort of solution is formed?
You said: alkaline
Which gas is produced when lithium reacts with water?
hydrogen
Which alkali metal is the most reactive out of lithium, sodium and potassium?
potassium
Why is sodium stored under oil?
You said: to keep it away from air and water
Which alkali metal is the softest out of lithium, sodium and potassium?
You said: potassium
How many chlorine atoms are there in one chlorine molecule?
two
Which of the properties below best describe the halogens?
You said: poor conductors of heat and electricity
Correct.
Which is the most reactive halogen?
flourine
Which of the statements below best describes the properties of the halogens as you go down group 7?
You said: The elements become less reactive and have higher melting points.
fluorine is more reactive than chlorine. What will happen when chlorine is bubbled through a solution of sodium flouride
Chlorine will not displace fluorine when chlorine is bubbled through a solution of sodium fluoride.
Why is neon used in neon lights?
You said: It gives off light when electricity passes through it.
Why is helium is used in balloons?
You said: It is less dense than air.
Which is the densest noble gas?
You said: radon
Correct.
The noble gases are monatomic. What does this mean?
they exist as single atoms
what is the group one metals aka
alkali metals
predict the electronic structure of first 20 elements
H:1 He:2
2,1 2,2 2,3 2,4 2,5 2,6 2,7 2,8
2,8,1 2,8,2 …………………………..
describe the main properties of halegons
low melting points and boiling points
meltijg and boiling points increase as you go down the group
reactivity decreses as you go down the group
At 25*C, fluorine and chlorine are gases, bromine is a liquid, and iodine and astatine are solids.
The halogens become darker as you go down the group.
why are group 0 elements or noble gases unreactive
they have a stable arrangement of electrons
An element has the electronic structure 2,8,4. Which group is it in?
You said: Group 4
Two elements have these electronic structures: 2,1 and 2,8,1. What can you say about the elements?
Elements with the electronic structures 2,1 and 2,8,1 are both in Group 1.
What do the elements in a group have the same number of?
same number of electrons in their outer shell.
What do the elements in a period have the same number of?
shells
Which of these electronic structures belongs to a noble gas?
2
When an element from group 1 reacts with water:
You said: A metal hydroxide and hydrogen are formed
describe the properties of group one (alkali metals)
as you go down the group:
atomic number increases
atomic mass increases
energy needed to remove an electron decreases
