topic 1- key concepts in chemistry Flashcards
What are the reactants? Which side are they located in a word equation?
The molecules that react with each other
(left-hand side of the equation)
What are the products? Which side are they located in a word equation?
what has been produced from the reactants
(right-hand side of the equation)
What is the atom made up of?
3 subatomic particles
electrons, protons & neutrons
Describe the 3 subatomic particles mass & how are they charged?
protons- heavy & positively charged
neutrons - heavy & neutral
electron - hardly any mass & negatively charged
Where is the nucleus found in an atom?
in the middle of the atom
What does the nucleus of an atom contain?
protons & neutrons
What is the charge of the nucleus?
positive charge (because of protons)
Where is most of the mass in atom concentrated in?
in the nucleus of the atom (from the protons & neutrons)
How big is the nucleus of the atom?
tiny when compared to the overall size of an atom
what do electrons do in the atom? And what do they move in?
they move around the nucleus in electron shells
What charge does electrons have?
they’re negatively charged
What is the difference between a electron and it’s shell?
they’re tiny but their shells cover a lot of space
What does the size of the shell of a subatomic particle determine?
size of the shell determines the size of the atom
What is atomic radius?
radius of atom
10 ^-10m
What’s an electrons mass sometimes considered as?
zero because it’s so small
What is the relative charge and relative mass of the subatomic particles?
protons- +1 -> 1
electrons- -1 -> 1/1840 (0.0005)
neutrons- 0 (no charge) -> 1
What is an atom?
an atom is the smallest part of an element that can exist
What is relative mass?
What is relative charges?
comparing the mass of an atom/molecule to a standard reference (protons in this case)
comparing the charges of different things with each other
What shape/volume does a gas have?
no fixed shape/ volume
Can/can’t gases be compressed? why?
can be compressed, because their particles are far apart and have space to move into
How do gases move and act in a container for example?
can flow & fill their container/space because their particles move quickly in all directions
What shape/volume does a liquid have?
a fixed volume but no fixed shape
How do liquids move and act in a container for example? Why can they do that?
can flow & take the shape of their container/space because their particles can move around each other
Can/can’t liquids be compressed? why?
cant be easily compressed because their particles are close together & have no space to move into
