topic 1- key concepts in chemistry

Question 1

What are the reactants? Which side are they located in a word equation?

Answer 1

The molecules that react with each other
(left-hand side of the equation)

Question 2

What are the products? Which side are they located in a word equation?

Answer 2

what has been produced from the reactants
(right-hand side of the equation)

Question 3

What is the atom made up of?

Answer 3

3 subatomic particles
electrons, protons & neutrons

Question 4

Describe the 3 subatomic particles mass & how are they charged?

Answer 4

protons- heavy & positively charged
neutrons - heavy & neutral
electron - hardly any mass & negatively charged

Question 5

Where is the nucleus found in an atom?

Answer 5

in the middle of the atom

Question 6

What does the nucleus of an atom contain?

Answer 6

protons & neutrons

Question 7

What is the charge of the nucleus?

Answer 7

positive charge (because of protons)

Question 8

Where is most of the mass in atom concentrated in?

Answer 8

in the nucleus of the atom (from the protons & neutrons)

Question 9

How big is the nucleus of the atom?

Answer 9

tiny when compared to the overall size of an atom

Question 10

what do electrons do in the atom? And what do they move in?

Answer 10

they move around the nucleus in electron shells

Question 11

What charge does electrons have?

Answer 11

they’re negatively charged

Question 12

What is the difference between a electron and it’s shell?

Answer 12

they’re tiny but their shells cover a lot of space

Question 13

What does the size of the shell of a subatomic particle determine?

Answer 13

size of the shell determines the size of the atom

Question 14

What is atomic radius?

Answer 14

radius of atom
10 ^-10m

Question 15

What’s an electrons mass sometimes considered as?

Answer 15

zero because it’s so small

Question 16

What is the relative charge and relative mass of the subatomic particles?

Answer 16

protons- +1 -> 1
electrons- -1 -> 1/1840 (0.0005)
neutrons- 0 (no charge) -> 1

Question 17

What is an atom?

Answer 17

an atom is the smallest part of an element that can exist

Question 18

What is relative mass?
What is relative charges?

Answer 18

comparing the mass of an atom/molecule to a standard reference (protons in this case)
comparing the charges of different things with each other

Question 19

What shape/volume does a gas have?

Answer 19

no fixed shape/ volume

Question 20

Can/can’t gases be compressed? why?

Answer 20

can be compressed, because their particles are far apart and have space to move into

Question 21

How do gases move and act in a container for example?

Answer 21

can flow & fill their container/space because their particles move quickly in all directions

Question 22

What shape/volume does a liquid have?

Answer 22

a fixed volume but no fixed shape

Question 23

How do liquids move and act in a container for example? Why can they do that?

Answer 23

can flow & take the shape of their container/space because their particles can move around each other

Question 24

Can/can’t liquids be compressed? why?

Answer 24

cant be easily compressed because their particles are close together & have no space to move into

Question 25

What shape/volume does a solid have?

Answer 25

a fixed volume and a fixed shape

Question 26

How do solids move and act in a container for example? What can’t they do? why?

Answer 26

cant flow, because their particles cannot move from place to place

Question 27

Can/can’t solids be compressed? why?

Answer 27

cant be compressed, because their particles are close together & have no space to move into

Question 28

what are the forces of attraction for solids?

Answer 28

strong forces of attraction

Question 29

what are the forces of attraction for liquids?

Answer 29

weak forces of attraction

Question 30

what are the forces of attraction for gases?

Answer 30

weakest forces of attraction