Chemistry Flashcards
How many Periods are there?
7
How are Periods and Groups arranged?
All elements in a Period are completely different, whereas elements in a Groups are arranged according to their properties.
What is a molecule?
2 or more atoms chemically bonded together.
What is an element made from?
It’s made of atoms or molecules.
What is a compound made of?
Molecules
What is the formula for Nitrogen and Chlorine?
N with a little 2
CL with a little 2
What does the Nucleus of an atom contain?
Protons and neutrons
What is the Nucleus of an atom?
It is the middle?
What type of charge does the Nucleus of an atom have?
It has a positive charge because of the protons.
What is around the Nucleus of an atom?
Shells along with electrons
What type of charge does an atom have?
Atoms have a 0 overall charge . They are neutral.
What type of charge does a Proton have?
+1 (positive)
What type of charge does a Neutron have?
0 (neutral)
What type of charge does an Electron have?
-1 (negative)
What is the relative mass of a proton?
1
What is the relative mass of a neutron?
1
What is the relative mass of an electron?
1/2000
How big is an atom?
Atoms are tiny. They are not visible from the human eye but they make up everything. Atoms are mostly empty space!
What does conservation of mass mean?
matter can’t be destroyed or created
What is a mixture?
2 or more substances that are NOT chemically joined together.
How do you work out the number of neutrons in an element?
Mass number - Atomic Number
Which number on an element is the atomic number?
The bottom number
Which number on an element is the mass number?
The top number
Number of protons = Number of electrons
True or False?
True
Why is the period number on a periodic table useful when making atoms structure?
It is the number of shells needed
Why is the group number on a periodic table useful when making atoms structure?
The number of electrons on the outer shell
If an atom is in group 0 how many electrons would go on the outer shell?
We would say group 8 instead so the maximum would be 8.
How are Ions formed?
When a metal reacts with a non-metal to create a compound
What is an Ion?
It’s the name we give to an atom that either a positive or negative charge.
How do you get a positive charge?
You will need more protons than electrons.
How do you get a negative charge?
You will need more electrons than protons.
How do you work out the number of neutrons?
mass number - atomic number
Which number on an element is the mass number?
the top number
How do you work out the mass number?
number of protons + number of neutrons
Which number on an element is the atomic number?
the bottom number
True or False?
Number of protons = Number of electrons
true
this means that atoms have no charge, they are neutral.
What do the period numbers on the periodic table mean when working out the electronic structure?
It’s the number of shells around the nucleus.
What do the group numbers on the periodic table mean when working out the electronic structure?
The number of electrons on the outer shell.
_____ form negative ions.
non-metals
What are negative ions called?
anions
What are positive ions called?
cations
How do atoms form negative ions?
They gain electrons
Do all metals conduct electricity?
Yes
How do Alkali metals react with water?
They dissolve and produce an alkali which makes the water turn purple and they fizz because they are making hydrogen.
What are some properties of Alkali metals?
Soft react with oxygen quickly shiny when freshly cut low melting point for a metal get more reactive down the group burn with different coloured flames form +1 ions
When group 1 metals react with water what do they produce?
an alkali (metal hydroxide) hydrogen gas
When group 1 metals react with oxygen what do they make?
metal oxide
What did Mendeleev do?
He arranged the elements known at the time in order of the relative atomic mass but he also noticed gaps in the table and predicted elements to fill them which he called eka-boron, eka-aluminium, eka-silicon, and eka-manganese.
What colour is chlorine?
pale green
What colour is bromine?
orange
what colour is iodine?
brown
what colour is fluorine?
pale yellow gas
what does displacement?
when a more reactive element swaps with a less reactive element.
What is the most reactive element in group 7 elements?
Iodine
