Atomic Structure
How many atoms of each element are in the compound Na2O?
2 sodium atoms and 1 oxygen atom
Name the state change when a solid becomes a liquid
Melting
What type of reaction is happening when the temperature increases?
Exothermic
What will happen to the rate of a reaction if the temperature is increased?
Increases
Give one observation when a strip of magnesium reacts with acid
Fizzing/gas produced OR temperature increase OR magnesium disappears
An atom contains 3 protons, 4 neutrons and 3 electrons. Which element is this atom?
Lithium
How many covalent bonds does each carbon atom form in diamond?
Four
Name the apparatus used to measure temperature
Thermometer
Hydrogen peroxide decomposes to produce water and oxygen. What is the word equation for this reaction?
Hydrogen peroxide --> Water + Oxygen
Define what is meant by an anomalous result
A result in an experiment that does not match the trend shown by the other results
Describe the plum pudding model of the atom
A ball of positive charge with negative electrons embedded in it
Name the type of bonding between a metal and non-metal element
Ionic bonding
A balance measures 6g even though there is nothing on it. What kind of error is this?
Zero error
To measure the rate of a reaction that produces a gas, what two aspects can we measure (along with time taken)?
Change in mass OR volume of gas produced
How do we calculate a mean?
Add up all the values, leaving out any anomalous results, then divide by the number of values
What is meant by the term "isotopes"?
Atoms with the same number of protons but different numbers of neutrons
Give two physical properties of diamond
Hard/strong OR high melting/boiling point OR does not conduct electricity
Name the energy needed to start a reaction
Activation energy
Explain how the presence of a catalyst affects the rate of reaction.
Reduces activation energy (by finding an alternative reaction pathway)
Give one way to improve the reliability of an experiment
Repeat results and calculate a mean
State how to calculate the number of neutrons in an atom
Describe how sodium metal conducts electricity
Delocalised electrons move throughout the structure, transferring energy
Explain, in terms of particles, why methane and oxygen do not react together at room temperature
The particles do not collide with enough energy to cause a reaction
Explain the benefit of using catalysts for chemical reactions in industry (do not refer to rate of reaction)
Less energy is needed, saving on energy costs
Calculate the mean of the following results: 6, 5, 7, 5, 5, 10, 4, 5, 5, 7, 7
5.6