science 2022 revision end of year

Question 1

daltons simple model has changed over time because of …

Answer 1

discovery of subatomic particles

Question 2

describe an atom

Answer 2

contains protons and neutrons

is surrounded by electrons in shells

Question 3

relative charge

protons -
nuetrons-
electrons

Answer 3

protons: +1
neutron : 0
electron: -1

Question 4

relative mass
protons -
neutrons-
electrons-

Answer 4

protons: 1
neutrons: 1
electrons: neglable (practically 0)

Question 5

is asked to calculate the mass pof an electron relative to a proton…

Answer 5

divide the 2 number thingys

Question 6

atoms have an equal amount of protons and electrons. true or false?

Answer 6

true

remember this by thingy about the relative charge cancel out

Question 7

what is the mass number

Answer 7

the total number of number of protons and neutrons in the nucleus

(top number)

Question 8

describe the atomic number

Answer 8

the number that says how many protons are in the nucleus

Question 9

what are isotopes

Answer 9

isotopes are atoms with the same number of protons but different number of neutrons

Question 10

how can you can recognise isotopes are the same element

Answer 10

they will have the same atomic number but different mass numbers

Question 11

why do isotopes have the same chemical properties

Answer 11

because they have the same number of electrons

Question 12

when was mendeleev’s table successful and developed into the modern periodic table ?

Answer 12

1869

Question 13

at the start how did mendeleev order the elements

Answer 13

relative atomic masses

Question 14

what did mendeleev do t make his periodic table more reliable

Answer 14

he checked the properties of the element and their compound

Question 15

what 2 things did mendeleev do to help his periodic table

Answer 15

• left gaps where he predicted elements to be

- he swapped the places of some elements so that elements with similar properties lined up

Question 16

on the modern periodic table what do the groups show

Answer 16

how many electrons are in the outer shell

Question 17

what do the periods show on the modern periodic table

Answer 17

how many shells are in use by the electrons

Question 18

what side are metals on left or right?

Answer 18

left

Question 19

what side are non-metals on , left or right?

Answer 19

right

Question 20

how many electrons are in the outer shell in group 0?

Answer 20

a full outer shell

Question 21

what is mitosis

Answer 21

a type of cell devision that takes place in several stages

Question 22

where does cell division happen in mitosis

Answer 22

in body cells

Question 23

what is a body cell

Answer 23

is any cell except those that produce gametes (sex cells)

Question 24

the cell that is dividing is called _____ and the two new cells that are formed are called _________

Answer 24

parent cell

daughter cells

Question 25

1) interphase

Answer 25

• chromosomes start to become visible

- DNA been copied

Question 26

2) prophase

Answer 26

• each chromosome consists of 2 chromatids

Question 27

3) metaphase

Answer 27

• nuclear membrane starts to break down

- chromosomes line up along the middle of the cell

Question 28

4) anaphase

Answer 28

• chromatids seperate
• one chromatid from each pair is pulled to each pole of the earth
• the chromatids can now be called chromosomes

Question 29

5) telophase

Answer 29

• cell spits into 2

- new nuclear membrane formed

Question 30

what is the word to help remember the stages of mitosis

Answer 30

IPMAT

Question 31

what is mitosis used for

Answer 31

growth, repair and asexual reproduction

Question 32

when do cells stop dividing

Answer 32

when growth has finished, except when repair is needed

Question 33

what does differentiation do

Answer 33

it creates specialised cells to carry out a function

Question 34

where do plant cells divide by mitosis

Answer 34

behind the tips and shoots and roots

Question 35

cell membrane

Answer 35

controls what enters and leaves the cell

Question 36

cytoplasm

Answer 36

reaction happen here

Question 37

mitochondria

Answer 37

where respiration takes place, relesing energy

Question 38

ribosomes

Answer 38

where proteins are made

Question 39

what are parts only in plant cells?

Answer 39

cell wall
centre vacuole
chloroplasts