Chemistry Flashcards
What is a compound?
Atoms of different elements chemically bonded together
What is a molecule?
More than one atom chemically bonded (may be the same element)
What is an atom?
The smallest stable part of an element
What is an element
Made out of one type of atom
What are the three states of matter?
Solid, liquid and gas
What is the particle theory?
A description on the movement and arrangement of particles
During a change of state, the temperature does not change even though it is still being heated, why?
The energy is being used to make the particles move more rather than to heat up
What is a melting point?
The temperature at which a solid changes to a liquid
What is a boiling point?
The temperature at which a liquid changes into a gas
Which states of matter have particles in a random arrangement?
Liquid and gas
Which states of matter have densely packed particles?
Solid and liquid
Why do substances have different melting and boiling points?
Some substances have stronger bonds between particles which require more energy to break
What is a condensing point?
The temperature at which a gas turns into a liquid
What is a freezing point?
The temperature at which a liquid turns into a solid
What is a pure substance?
A substance which has nothing added to it, it is in it’s natural state
What is a formulation?
A mixture which has been designed to create a useful product
How do you separate salt from water?
Evaporate the water into another container, water has a lower boiling point than salt. Condense the steam to get water back
How do you separate sand from water?
Use a filter paper and funnel and pour the water and sand in, the water will go through and the sand will get stuck
What does immiscible mean?
Doesn’t mix
What does miscible mean?
Does mix
How do you measure the distance a substance moves in chromatography?
Distance travelled by sample
__________________________________
Distance travelled by the solvent
How does each group affect charge on ions
Group 1: 1+
Group 2: 2+
Group 3: 3+
Group 4: doesn’t form ions
Group 5: 3-
Group 6: 2-
Group 7: 1-
Group 0: never form ions
Name the formula for the following:
Hydroxide
Nitrate
Carbonate
Sulphate
Phosphate
Ammonium
Hydroxide: OH -
Nitrate: NO3 -
Carbonate: CO3 2-
Sulphate: SO4 2-
Phosphate: PO4 3-
Ammonium NH4 +
Do atoms have positive, neutral or negative charge?
Neutral charge
Number of protons = ?
Atomic number
Number of neutrons = ?
Mass number - atomic number
Number of electrons = ?
Mass number
What is an isotope?
2 or more forms of an element with the same number of protons but different number of neutrons