C9 - Periodic Table Flashcards
How are elements ordered in the periodic table? [1]
By increasing atomic number (number of protons)
What are vertical columns in the periodic table called? [1]
Groups
What are horizontal rows in the periodic table called? [1]
Periods
What is the trend in metallic character across a period? [1]
A gradual change from metal to no-metal
What happens to the number of electrons in the outer shell of an element across a period? [1]
It increases
What happens to the structure of an element across a period? [1]
Giant metallic (e.g. Li) - giant covalent (e.g. C) - simple molecular (e.g. Ne)
Why do elements in the same group react in a similar way? [1]
They have the same number of electrons in the outer shell.
What is the same for elements in the same period? [1]
They have the same number of shells of electrons
What are the properties of group 1 elements (the alkali metals)? [2]
They are good conductors of heat and electricity, they are soft metals
What are the trends in group 1 as you go down the group? [3]
Reactivity increases, density increases, melting point decreases
Write the balanced symbol equation for the reaction of lithium with oxygen [1]
4Li (s) + O₂ (g) → 2Li₂O (s)
Write the balanced symbol equation for the reaction of sodium with water [1]
2Na (s) + 2H₂O (l) → 2NaOH (aq) + H₂ (g)
Write the balanced symbol equation for the reaction of rubidium with chlorine [1]
2Rb (s) + Cl₂ (g) → 2RbCl (s)
Describe the appearance of the halogens chlorine, bromine and iodine [3]
Chlorine is a pale yellow-green gas, bromine is a red-brown liquid, Iodine is a grey-black solid
The halogens are diatomic, describe what this means [1]
There are two atoms in the molecule (e.g Cl₂)
What are the trends in group 7 as you go down the group? [3]
Reactivity decreases, melting point increases, they become darker
Write the balanced symbol equation for the reaction of chlorine and hydrogen [1]
H₂ (g) + Cl₂ (g) → 2HCl (g)
Write the balanced symbol equation for the reaction of chlorine with iron (III)
2Fe (s) + 3Cl₂ (g) → 2FeCl₃ (s)
Describe what happens in a displacement reaction
A more reactive element displaces a less reactive element from a compound
Write the balanced symbol equation for the displacement reaction between potassium iodide and chlorine [1]
2KI (aq) + Cl₂ → 2KCl (aq) + I₂ (aq)
Describe the properties of transition metals [5]
High density, high melting point, good conductors, form coloured compounds, can act as catalysts
Describe the noble gases (group 8/0) [1]
Unreactive monoatomic gases
Explain why the noble gases are unreactive? [1]
They have a full outer shell of electrons
Describe the uses of halogens [2]
Argon in lamps, helium in balloons
