Chemistry Flashcards
What is an element?
A substance that contains only one type of atom.
Can elements be broken down into other substances?
no, because since the substance breaks down when electricity passes through it, it can’t be an element.
What is an atom?
They are the smallest parts of elements that can exist. They make up everything physical and are too small for us to see.
What is a compound?
It is a pure substance which is made up of atoms of 2 or more elements.
What does hydrogen go round in?
Pairs
What is hydrogen?
An element which is a gas at room temperature, when mixed with air and ignited with a spark it will explode.
What is a molecule?
It is 2 or more atoms strongly bonded together.
What is oxygen?
An element which exists as molecules of 2 atoms. It is also a gas at room temperature, with no colour or smell.
What is water?
It is a molecule made up of two elements , hydrogen and oxygen. Therefore, water is a compound.
Why are water molecules different to oxygen and hydrogen molecules?
Because water has a higher boiling point than the others so it is a liquid.
If it ends with ate what does it have?
Oxygen
How many atoms are there in a molecule of water?
3
Compounds made up of oxygen and another element have ___ ____ _____. What is the second word called?
two word names. The second word is oxide. etc. aluminium + oxygen = aluminium oxide.
When does the Elements name change to ide?
when a metal and non-metal combined.
oxygen -
nitrogen - ?
sulphur - ?
ine - ?
oxide.
nitride.
sulphide.
ide.
For compounds containing ___ elements and oxygen the ending of the other _________ changes to ___.
- 2
- Non-metal
- ate
What is a chemical formula?
It shows the elements present in a compound, as well as the number of atoms of each element.
Hydroxides - ?
Nitrates - ?
Sulphates - ?
Carbonates - ?
OH
NO3
SO4
CO3
Mono -
Di -
Tri -
1
2
3
What is a Polymer?
A polymer is a VERY large molecule made up from repeating units/ monomers.
What is a natural polymer?
Polymers made by plants and animals, like wool, cotton, starch and rubber.
What is a synthetic polymer?
Polymers made in chemical reactions.
What is a monomer?
A molecule that can be bonded to other identical molecules to form a polymer.
What are vertical columns called in the periodic table?
Groups
What are horizontal rows called in the periodic table?
Periods
What does the periodic table arrange the elements in?
It arranges them in groups according to their properties.
Group 1 - periodic table: Give an example of what the elements in group 1 are used for.
Batteries, fireworks
Group 1 - periodic table: What are the elements called?
Alkali metals
Group 1 - periodic table: The elements are called Alkali metals, but which one is not a metal?
Hydrogen
Who created the Periodic Table?
Mendeleev
Periodic Table: If the elements are on the left of the staircase what does that indicate?
That they are metals
Group 1 - periodic table: The boiling point and melting point increases/ decreases from bottom to top/ top to bottom.- choose
Decreases, top to bottom
Group 1 - periodic table: When the elements react with water what do they produce?
Hydrogen gas, which moves the elements around on the surface.
Group 1 - periodic table: Why does the water turn purple when the elements come in contact with it?
Because they make alkaline solution.
Group 1 - periodic table: What is the pattern with the reactions?
It gets vigorous as you go down the table.
Group 1 - periodic table: What are the affects in common with lithium, sodium and potassium?
They all fizz which means gas is being made in a chemical reaction, move and the water turns purple because of the alkali. When you put any of them in.
Rubidium and caesium are also Group 1 elements. Predict what observations you would see if they reacted with water.
Rubidium would cause more fizzing than the rest and maybe also catch on fire more than potassium.
Caesium would cause even more fizzing and would cause a bigger fire than Rubidium.
Periodic Table: What scientist came up with the law of octaves?
Newlands
What are group 7 elements on the periodic table known as?
Halogens
What are group 0 elements on the periodic table known as?
Noble gases
Group 7 and 0- As you go down the group what happens to the melting point, boiling point and density.
They all increase
Group 7- What happens to the colour?
It gets darker
Group 7- What order do they go in, state wise?
gas, liquid, solid.
What does diatomic mean?
where atoms are lonely and pair up
Group 7- toxic or non-toxic
non-metallic or metallic
toxic- they can kill cells
non- metallic
Group 7- Are they good heat and electricity conductors
No
During a displacement ____ an element will replace a ____ reactive element in a ________. ______ also do this.
reaction
less
compound
Metals
Group 7- Reactivity increases/ decreases down/ up the group. Reactions become more/ less vigorous
decreases
down
less
Group 7- Sodium bromide + chlorine –> ?
Potassium iodide + Fluorine –> ?
Lithium bromide + iodine –> ?
Sodium chloride + bromine
Potassium fluoride + iodine
Lithium bromide + iodine
Group 0- Don’t / do anything
Don’t
What does inert mean?
unreactive
Group 0- Do they pair up- monatomic
No therefore, they are not molecules
Group 0- As you go down the group the elements get slightly/ very reactive. ______ and ____ don’t react at all.
Slightly
Helium
Neon
Group 0- The smaller the _______ the more they _____.
density
float
What is a mixture?
A mixtures is a substance that is made up of two or more elements not joined together
