End Of Unit Questions Flashcards
How was Mendeleev’s periodic table an improvement on Newlands table?
The elements fitted the groups better, allowed for undiscovered elements
Why do elements in the groups of the modern periodic table have similar properties?
They have the same number of electrons on their outer shells
A small piece of lithium is added to a bowl of water. Write a word equation for the reaction of lithium with water
Lithium + water –> lithium hydroxide + hydrogen
A small piece of lithium is added to a bowl of water. Describe 3 things you would see when the lithium is added to the water
Lithium floats, moves around the surface, gradually disappears, bubbles or fizzes
A small piece of lithium is added to a bowl of water. How could you show that an alkali has been produced?
Add universal indicator, goes purple or blue
A small piece of lithium is added to a bowl of water. Give one way the reaction of sodium with water is different to the reaction of lithium with water
Sodium reacts faster, lithium does not melt
Predict 3 physical and 3 chemical properties of the transition metal cobalt
Physical: high mp and bp, hard, strong, high density, malleable, ductile, good conductor
Chemical: unreactive, forms positive ions, coloured compounds, differently charged ions, catalyst
What is the trend in melting and boiling points going down group 7?
They increase
What is the formula of sodium bromide? Describe its appearance and what happens when it is mixed with water
NaBr, colourless or white, crystals or solid, dissolves in water, forms a colourless solution
Hydrogen chloride is a gas at room temp. Explain why
Covalently bonded, small molecules with weak intermolecular forces
Some chlorine water was added to an aqueous solution of potassium bromide. Describe the colour change that you would see
From colourless to orangey brown
Some chlorine water was added to an aqueous solution of potassium bromide. Write a word equation for the reaction that happens
Chlorine + potassium bromide –> potassium chloride + bromine
Some chlorine water was added to an aqueous solution of potassium bromide. Write a balanced symbol equation for the reaction
CL2 + 2KBr –> 2CL + Br2
Iron reacts with chlorine to produce iron(III) chloride. Write a balanced symbol equation for this reaction
2Fe + 3CL2 –> 2FeCL3
Explain in terms of electronic structures why sodium is more reactive than lithium
A sodium atom has more shells so there is a weaker attraction between the outer electrons and the nucleus so can be more easily lost when it reacts
