Matter
All matter is made up of _____ which are in turn made up of _____, ______ and __________.
Atoms which are made of protons, neutrons and electrons.
What is the difference between mass and weight?
Mass is the amount of matter that makes up an object. It doesn't change depending on the gravity of the planet it is on. Whereas weight is the force of gravity impacting an object so people can bounce higher on the moon due to having less weight there but not less mass.
What does the Atomic Number indicate about an element?
The number of protons it has. It is unique to that element.
The reactants are written on the left hand side or right hand side of the arrow in a reaction?
The left hand side
On which axis do you usually plot the dependent variable?
y-axis
Name the states of matter and give an example from the periodic table of different elements that have this state.
Solids - any metal, some non-metals
Liquids - mercury or bromine
Gas - any noble gas and some non-metals
Imagine you had a piece of aluminium foil scrunched up into a ball. This will float on water. Explain how you could change it's density and make it sink.
You could compress it further by squeezing all the air out of it and therefore reduce its volume.
Give an example of an element that has two letters in its Atomic Symbol.
Cu
Co
Fe etc.
What does the small number (subscript) in CO2 mean?
There are two oxygen atoms for every one carbon atom.
Define: reliability, validity and accuracy.
Reliability - how close the results are to one another.
Validity - whether you controlled variables well and therefore measured what you intended to measure.
Accuracy - how closely your results match to the well known/ accepted value.
Explain what the difference is between matter and energy.
Matter is physical things that are made of atoms. We don't always have to see it (like air). Energy is a force that can affect matter (like a magnet moving iron nails).
What is the density formula?
d=m/v
Name one element that is named after a person.
Einsteinium
Mendelevium
Curium etc.
Name one chemical reaction you know of.
Examples could include:
- combustion (burning)
- respiration
- photosynthesis
- rusting (corrosion) etc.
What is one advantage of line graphs compared to column graphs when plotting data like time, a continuous variable?
It allows you to make predictions between time poitns. E.g. if you took measurements every day you could predict what the value would be every half a day.
An atom is one type of element e.g. iron whereas a compound is two different elements bound together e.g. carbon dioxide.
The density decreases as the particles move more and have more space between them and therefore increase the volume for the same mass.
Give one reason that the Periodic Table of elements is useful to scientists.
It allows communication to be easier as it is used all over the world.
It is a reference of all known elements in the universe.
It allows patterns to be observed and therefore predictions to be made.
True or False: in a chemical reaction the number of atoms before the arrow and after the arrow are always equal?
True - this is called the conservation of mass. All matter remains the same it simply re-arranges itself in a reaction.
What does it mean that there is a "law" of the conservation of mass? I.e. what is the law part of that sentence mean?
It means there is a mathematical relationship defining how mass is always conserved in a reaction.
Give an example of a compound with different properties to the elements that make it up.
Salt (sodium chloride) is very different to sodium (an explosive metal) and chlorine (a green toxic gas)
Why is it incorrect to say that heavy things sink in water?
Because a ship is heavy and yet it floats. It is not to do with heaviness but density.
Why is the Periodic Table called the Periodic Table?
Because it is arranged in Periods or columns (which are related to the valency of electrons).
Write out the word equation for either photosynthesis or respiration.
Photosynthesis: carbon dioxide + water -> glucose + oxygen
Respiration: glucose + oxgygen -> ATP (energy) + carbon dioxide + water
Because you could obtain different results. Repeating allows you to judge reliability.