4.5.1 The Periodic Table - Flashcards
How are the elements arranged in the periodic table?
In order of increasing atomic number
What do elements in the same group (column) of the periodic table have in common with each other?
They have the same amount of electrons in the outer shell i.e. all the elements in group 6 have 6 electrons in the outer shell
What do elements in the same period (row) of the periodic table have in common with each other?
They have the same amount of shells i.e. all the elements in period 3 have 3 shells.
What are the three rules for drawing electrons in electron shells?
- You fill up from the inner shell first.
- The middle shell can only have 2 electrons.
- All other shells can have 8 electrons.
Use the periodic table. How many electrons does the element Aluminium have?
13 (it is the proton or atomic number of the element)
Magnesium has 12 electrons. What will its electron configuration (electron shells) look like?
2, 8, 2
Who designed the modern periodic table?
Dimitri Mendeleev
How did Dimitri Mendeleev order the elements in the periodic table? Why was this a problem?
He put them in order of atomic mass. This meant some elements appeared to be in the wrong group and did not have similar properties to the rest of the elements in the group/
What do we call the middle of an atom?
The nucleus
Which sub atomic particles are found in the nucleus?
Protons and neutrons
What is the definition of an isotope?
Elements with the same amount of protons and electrons, and a different amount of neutrons
What is an element?
A substance made of one type of atom
What is the charge on an electron?
Negative
What is the charge on a proton?
positive
What is the charge on a neutron?
Neutral
What is a compound?
Two or more elements chemically bonded together
Where are metals found on the periodic table?
On the left of the periodic table
Metals are usually found in groups 1,2,3 and 4 of the periodic table. What will happen, in terms of electrons, to these elements when they react?
They will lose electrons to achieve an empty outer shell which is stable.
How many electrons does an element want in its outer shell to be stable?
8 (unless it is the middle shell then 2 electrons)
What charge will the ion be if an element gains an electron?
Negative - as electrons have a negative charge and it will have an extra electron.
What charge will the ion be if an element loses an electron?
Positive - as electrons have a negative charge and it will have lost an electron.
Which type of elements gain electrons when they react?
Non metals
What do we call the group 0 elements?
Noble gases
Why are group 0 elements so unreactive?
They have full outer shells
What is the trend in boiling point in group 0?
As the group 0 elements have a higher atomic mass (down the group) the boiling point increases
What are the group 1 metals called?
The alkali metals
Why are the group 1 metals called the alkali metals
When they react with water they produce hydroxides (OH-) which are alkaline (will turn universal indicator purple)
Group 1 elements are stored in oil. Why?
They are very reactive with both water and oxygen.
Group 1 elements are unusual metals. Why?
They are very soft and have a low density
What is made when a group 1 metal reacts with water? i.e. Lithium + Water –>
A hydroxide and hydrogen gas
–> Lithium Hydroxide + Hydrogen
What is the reactivity trend in Group 1?
As you go down group 1 the elements get more reactive. The reactions with water become more violent.
Why do the group 1 elements get more reactive down the group?
The elements all lose an electron when they react. It is easier to lose an electron from a big atom (Like potassium) as the electron is further away from the nucleus so it less attracted to the nucleus. Also the inner electrons shield the outer electron from the attraction to the nucleus. This means this electron is less attracted and can more easily be lost than in a small atom like Lithium.
What do we call the group 7 elements?
The Halogens
The reactivity trend in group 7 is opposite to group 1. Why?
Group 1 elements are trying to lose 1 electron. Group 7 elements are trying to gain 1 electron when they react. This means a smaller atom finds it easier to attract an electron as there are less electrons shielding the attraction to the nucleus.
What do we call the type of reaction where a more reactive halogen swaps a lesson reactive halogen from a solution of its salt?
A displacement reaction
Why is an atom neutral overall?
It has the same amount of positive protons and negative electrons.
