Chemistry 2b Topics 4, 5 & 6 Flashcards
Describe the structure of a metal.
They are made up of lots of metal atoms held together by metallic bonds
Is this statement true or false? “Alkali metals have high melting points”.
Fales
Give two normal properties of metals
They’re malleable and conduct electricity well
Potassium is a group 1 element. When placed in water, potassium reacts quickly. What gas is made by this reaction?
Hydrogen
What colour is bromine at room temperature?
Orange
Do hydrogen halides dissolve in water to form acidic or alkaline solutions?
Acidic solutions
Name two noble gases and state a use for each
Argon is used to provide an inert atmosphere in light bulbs, helium is used for balloons.
Is this true or false? “The boiling point of the noble gases decreases as you go down the group”
False
What is an exothermic reaction? Give two examples
An exothermic reaction is one which overall gives out energy in the form of heat. It’s shown by a rise in temperature, e.g. Burning fuels and explosions
Give two examples of an endothermic reaction
Photosynthesis and ammonium nitrate dissolving in water
How would you measure the temperature change during a neutralisation reaction?
You take the temperature of the reactants, then mix them in a cup. Finally measure the temperature of the solution at set points during the reaction
What are the four factors that affect the rate of a reaction?
Temperature, concentration of co2, catalyst, surface area of a solid
What is the effect of increasing temperature on the rate of a reaction?
The higher the temperature the faster the rate of reaction
What is a catalyst?
A catalyst is a substance which changes the speed of a reaction, without being used up in the reaction.
What is the role of a catalytic converter car exhausts?
A catalytic converter increases the rate of which carbon monoxide and unburnt fuel in exhaust gases react with oxygen in the air
