C2.2 Flashcards
How can you differentiate between metal and non metal oxides?
Metal oxides are alkaline, non metal pxides are acidic
What side of the periodic table is non-gases
Right side,although hydrogen is on the left
What are properties of metal?
Shiny High melting/boiling point Solid at room temp Malleable Ductile Conductors
What does a period tell you about an element?
The period is the number of electron shells
What does a group tell you about an element?
The group is the number of electrons in the outer shell (non IUPAC)
What is the electron structure of an element with 15 electrons?
2.8.5
If an element loses electrons,what charge does it become?
Positive
If an element gains electrons,what charge does it become?
Negative
How do you draw dot and cross diagrams for ionic compounds
Draw the outer shell of each atom
With one element being crosses and the other dots
One shell should be empty and the other full
Brackets outside the atom and shells with a + or - charge and magnitude (e.g +2)
What are the limits of electrons in each shell?
Shell 1 - 2
Shell 2 - 8
Shell 3 - 8
Shell 4 - 16
If an element X with 15 electrons reacts with an element Y with 13 electrons,what happens?
Y gives 3 electrons to X
They both stabilise and become positive or negatively charged
Forces of attraction bring them together
What is the structure of ionic compounds?
Giant ionic lattice, positive and negative ions in a regular arrangement and alternating
What is a simple molecule
A molecule with only a few atoms
What is a covalent bond?
When 2 non-metals share electrons to become stable
Give an example of a double covalent bond
Carbon dioxide (CO2)
Why is the melting point of simple bolecules low even though they have covalent bonds?
Even though they have strong covalent bonds the intermolecular forces between the molecules are weak
What is a giant covalent structure?
Many non metal atoms joined by covalent bonds,arranged in a repeating regular pattern called a giant lattice
Why does diamond have a high melting point?
The atoms are covalently bonded and require a lot of energy to break apart
Why is the empirical formula of Diamond and Graphite just C?
The only atoms are carbon (C), so instead of writing a high number it can just be simplified to C
What are polymers?
Monomers joined together by covalent bonds, end to end in a long chain
How do you convert a monomer displayed formula to a polymer displayed formula?
Remove a covalent bond from the middle,and add one reaching out on both edges
Put the formula in a bracket with n written in subscript
What is the difference between thermosoftening and thermosetting polymers
In thermosoftening, polymers are simply tangled together with no extra bonds, so they have e,g a low melting point.
In thermosetting,polymers are joined by strong crosslinks (covalent bonds) , so they have e.g a high melting point
What is the structure of metals like?
Atoms packed together in a giant metallic lattice
What are metallic bonds?
Metal atoms lose electrons from their outer shell, which become delocalised.
There are forces of attraction between positive metal ions and delocalised electrons
Why can metal ions conduct electricity?
Due to delocalised electrons which can carry charge
How did Mendeleev initially arrange the periodic table?
He arranged in increasing atomic weight, but switched some elements around to fit their properties
And he grouped elements with similar properties
How is the modern periodic table arranged?
In order of increasing atomic number (protons)
Why are some elements more reactive than others?
It depends on how many electrons they need to gain/ lose to become stable,if it is more then they will be more desperate for reaction
What are halogens?
The elements in group 7
Why would an element with 20 electrons and an element with 12 electrons have different reactivity but still the same number of electrons in the outer shell?
The element with 20 electrons would be more reactive as the outer shell is further from the nucleus so it would lose those electrons easier
