Each question in this quiz is timed.
In the equation Q = mcΔT, what does c stand for?
Energy released
Mass heated
Specific heat capacity
Change in temperature
In the equation Q = mcΔT, what does ΔT stand for?
True or false? To find out the energy released per gram, we measure the change of mass in fuel and divide by that value.
True or false? To find the energy released per mole, we divide the energy released per gram by the relative formula mass of the substance.
Why do simple calorimeters not give an accurate reading for temperature change?
They do not have sophisticated data loggers
A lot of thermal energy is not transferred to the solution in the calorimeter
The calorimeter only allows pre-set temperature changes to occur
Which of these are features of a simple calorimeter?
Cup made of copper
Cup made of polystyrene
No lid is present
A lid is present
What would be the correct equation if 50g of acid was mixed with 50g of alkali causing a temperature rise of 9°C?
Q = 50 * 4.2 * 9
Q = 100 * 4.2 * 9
Q = 100 * 8.4 * 9
Q = 50 * 8.4 * 9
True or false? When measuring energy changes in solutions, we assume the solution behaves like water.
In an exothermic reaction, which side of the energy level diagram has more energy?
Reactants
Products
In an endothermic reaction, which side of the energy level diagram has more energy?
True or false? The energy change of a reaction is the difference between the maximum activation energy and the energy of the products.
How would an energy level diagram be different if a catalyst were present?
The activation energy would be higher
The activation energy would be lower
The reactants would have less energy
The products would have more energy
True or false? Bond breaking is exothermic.
What unit are bond energies measured in?
kJ
kJ/g
kJ/mol
kJ/cm^3
True or false? The bond energy needed to break a particular bond is the same as the bond energy released in forming that bond.
What is the ΔH of a reaction?
The bond energy of forming products - the bond energy of breaking reactants
The bond energy of breaking reactants - the bond energy of forming products
The bond energy of forming reactants - the bond energy of breaking products
The bond energy of breaking products - the bond energy of forming reactants
Which gas is being looked at as a possible alternative to petrol fuels?
Oxygen
Nitrogen
Hydrogen
Carbon dioxide
True or false? The only waste product of the combustion of hydrogen is water.
What do we use to combust hydrogen?
Internal combustion engine
Fuel cell
Downs cell
Which of these are disadvantages of using hydrogen as a fuel?
It is not very inflammable
There are safety problems due to flammability
It takes up a lot of storage space
At present we only have a limited supply
Hydrogen is toxic to humans
