sci (๑•̀ㅂ•́)و✧ Flashcards
2024
1
Q
science definition
A
Science is a discipline that involves systematic observations and experiments of natural phenomena.
2
Q
boiling tube function
A
heat small amounts of chemicals
3
Q
test tube function
A
hold small amounts of chemicals
4
Q
what can be used to contain larger amounts of chemicals
A
beaker
conical flask
flat-bottom flask
5
Q
evaporating dish
A
evaporate excess solvent
6
Q
crucible and lid
A
used to heat solids directly over a flame
7
Q
filter funnel
A
separate insoluble solids from mixtures
8
Q
gas jar
A
contain gas
9
Q
measuring cylinder
A
measure volume of liquid
10
Q
wire gauze
A
spreads heat evenly during heating
11
Q
tripod stand
A
support apparatus during heating
12
Q
retort stand with clamp
A
holds or supports apparatus
13
Q
burette
A
measure volume of liquid accurately
14
Q
pipette
A
measure fixed volume of liquid
15
Q
bunsen burner
A
provide flame to heat substances
16
Q
flat-bottom flask
A
contain chemicals used in preparing gases if the process requires no heating.
17
Q
round-bottom flask
A
contain chemicals used in preparing gases if the process requires heating.
18
Q
irritant
A
give out vapour or fumes that will hurt the eyes, nose and throat
19
Q
radioactive
A
emit radioactive rays
20
Q
corrosive
A
burns skin
21
Q
flammable
A
easily vaporises
keep away from fire/heat
22
Q
5 physical quantities
A
length
mass
time
temperature
electric current
23
Q
SI unit for length
A
metre/m
24
Q
SI unit for mass
A
kilogram/kg
25
SI unit for time
second/s
26
SI unit for temperature
kelvin/K
27
SI unit for electric current
ampere/A
28
value of giga/G
1 000 000 000/10⁹
29
value of mega/M
1 000 000/10⁶
30
value of kilo/k
1 000/10³
31
value of deci/d
0.1/10-¹
32
value of centi/c
0.01/10-²
33
value of milli/m
0.001/10-³
34
value of micro/μ
0.000 001/10-⁶
35
value of nano/n
0.000 000 001/10-⁹
36
how to avoid parallax error/random error
look at the scale reading perpendicular to your eyes
take a few readings and take the average reading
37
how to avoid systematic errors
repeat the experiment using different measuring instruments
38
what method is used to measure volume of irregular shapes
water displacement method
39
density definition
mass per unit volume of a material
40
density formula
density = mass/volume
41
why does a cork float in water
the cork is less dense than the water
42
why does a stone sink in water
the stone is denser than the water
43
steps in a scientific investigation in order
1. identify a problem
2. construct a hypothesis
3. control variables
4. plan an experiment
5. conduct the experiment
6. collect data
7. analyse and interpret data
8. make a conclusion
9. write a report
44
who discovered cells
Robert Hooke
45
what causes cancer to occur
cancer occurs when normal cells divide continuously without control.
46
how do cells form new cells
cell division
47
steps to observe cheek cells
1. Put a drop of distilled water onto a glass slide
2. scrape the inside of the cheek
3. place the cells onto the glass slide
4. add a drop of methylene blue solution on the cells
5. gently place a cover glass on top of the glass slide using a mounting needle to make sure there are no air bubbles.
6. use a filter paper to absorb excess methylene blue solution
7. observe the glass slide under a microscope
48
steps to observe onion cells
1. peel a later of epidermis from an onion
2. put the epidermis layer onto a glass slide
3. add a drop of iodine solution on the epidermis layer
4. gently place a cover glass on top of the glass slide using a mounting needle to make sure there are no air bubbles.
5. use a filter paper to absorb excess iodine
6. observe the glass slide under a microscope
49
name the parts in animal cell
nucleus
mitochondria
cytoplasm
cell membrane
50
name the parts in plant cell
nucleus
mitochondria
cytoplasm
cell membrane
vacuole
cell wall
chloroplast
51
function of cell membrane
controls the flow of materials in and out of the cell
52
function of mitochondria
produces energy
53
function of nucleus
controls all activities in the cell
contains genetic information
54
function of cytoplasm
place where chemical reactions occur
55
chloroplast
absorbs light energy to carry out photosynthesis
56
cell wall
provides support
57
vacuole
provides support to cells when filled with cell sap
58
multicellular microorganisms
Mucor
Spirogyra
Hydra
59
epithelium cells
skin
form a later that protects organs
secrete mucus
60
white blood cells
changes its form to surround foreign particles and destroy them
61
muscle cells
contract and relax to enable movement
62
nerve cells
sends information in the form of impulse to the body
63
red blood cells
no nucleus
biconcave disc shaped - increase surface area
contain haemoglobin to transport oxygen to the body
64
epidermal cells
reduce water loss
allow gaseous exchange
absorption of water & nutrients
65
palisade cells
contain chlorophyll
66
guard cells
control opening and closing of stoma (hole)
open during the day to carry out photosynthesis
closed at night/hot day
67
root hair cells
increase surface area to absorb water and nutrients from the soil
68
order of cell organisation
cell -> tissue -> organ -> system -> organism
69
lymphatic system
drains lymphatic fluid into blood vessels
protect the body from infections
70
digestive system
breaks down food into simpler form
71
integumentary system
(skin)
regulates body temperature and water content
72
blood circulatory system
carries oxygen, nutrients and hormones to the whole body
73
respiratory system
absorbs oxygen and releases carbon dioxide
74
endocrine system
produces hormones
organs:
pituitary
thyroid
adrenal pancreas
ovary
testis
75
excretory system
removes excretory waste
76
skeletal system
supports and protects the body and organs
77
respiration definition
respiration can be divided into
internal respiration (breathing)
and external respiration (cell respiration)
78
external respiration/breathing
exchange of gases
79
internal respiration/cell respiration
process of breaking down food to release energy
80
cell respiration word equation
glucose + oxygen ----> water + energy + carbon dioxide
81
steps to test the presence of starch
1. dip the leaf in boiling water to soften it
2. put the leaf in a boiling tube filled with ethanol
3. put the boiling tube into a beaker containing hot water
4. after 5 minutes, take the leaf out and observe the colour changes
5. dip the leaf into the hot water to soften it
6. place the leaf on a white tile and put a few drops of iodine solution on it
if there is presence of starch, the iodine solution's colour will change from brown to dark blue
82
photosynthesis word equation
carbon dioxide + water --light energy (top of arrow), chlorophyll (bottom of arrow)----> oxygen + glucose
83
corrective mechanism when water increases
brain stimulates the production of hormone so that the kidneys produce more urine
84
corrective mechanism when water decreases
brain stimulates the production of hormone so that the kidneys produce less urine
feel thirsty
85
corrective mechanism when temperature increases
hairs lay flat
blood vessels dilate
increase sweating
skeletal muscle activity and certain hormone secretion will reduce
less urine
86
corrective mechanism when temperature decreases
hairs stand erect
blood vessels constrict
decrease sweating
skeletal muscles will contract and relax actively, causing shivering
hormones will be secreted to increase body metabolism
87
how do plants lose water
transpiration process
88
benefits of transpiration
helps to absorb and carry water and minerals
evaporation of water cools the plant during hot days
89
budding
a bud forms as a swelling, then it develops and breaks off as a new young
Hydra
90
binary fission
division of a single parent cell into two daughter cells
Amoeba, Paramecium, bacteria
91
regeneration
fragments of some organisms develop and grow into new individuals
starfish, Planaria, flatworm
92
spore formation
producing spores in sporangium
after sporangium breaks, spores get scattered by the wind
when they land in a moist place, they grow into new plants
algae, fungus, fern, bacteria
93
vegetative reproduction
producing new plants from a vegetative part of a plant except the flower
root, stem, leaf
94
characteristics of male gamete
head
nucleus
middle piece
tail
able to move
smallest cell in the male's body
live up to 3-4 days
95
characteristics of female gamete
gel layer
nucleus
cytoplasm
cell membrane
not able to move
largest cell in the female's body
live up to 2 days
95
menstruation phase
day 1-5
uterine lining breaks down and is discharged together with blood, unfertilised ovum and mucus
96
repair phase
day 6-11
uterine lining thickens
97
fertile phase
day 12-17
ovum is released on the 14th day (ovulation)
uterine lining thickens
98
premenstrual phase
day 18-28
uterine lining continues to thicken
99
effects of irregular menstruation
infertility
difficulties in family planning
health problems such as anaemia
100
function of uterus
place where embryo develops and grows
101
function of fallopian tube
place where fertilisation between sperm and ovum occurs
102
ovary
produces female gamete and female sex hormones
103
cervix
produces mucus to enable sperms to swim into the uterus
104
vagina
recieves sperms and is a channel which a baby is born
105
seminal vesicle
secretes nutritional fluid for the sperms
106
urethra
channel to discharge sperms and urine
107
sperm duct
transports sperms from the testis to the urethra
108
penis
transfers sperms into the vagina during copulation
109
scrotum
holds and protects testes
110
testis
produces male gamete and male sex hormones
111
prostate gland
secrete fluid which contains nutrients and protects sperm cell
112
flow chart for development of zygote
zygote -> embryo -> foetus -> baby
113
placenta
Place where exchange of oxygen and carbon dioxide, supply of nutrients and removal of waste materials through the mother’s blood and the foetus occur
114
umbilical cord
tube which connects the foetus to the placenta
has blood vessels inside to transport blood to and from the foetus
115
uterine wall
consists of muscular wall
place where the embryo is implanted and develops
116
amnion
membrane that forms a sac and contains fluid
117
amniotic fluid
acts as a cushion to absorb concussion and protects the foetus from injuries
118
Effects of smoking while pregnant
Baby low birth weight
Baby higher mortality rate
Baby may become retarded/have physical difficulties
Baby may be premature
Miscarriage of foetus
119
Effects of taking drugs while pregnant
Foetal defects
120
Effects of drinking alcohol while pregnant
Baby born with Foetal Alcohol Syndrome
Delayed foetal development
Brain, nervous system and heart may be damaged
121
Breast milk or formula milk??
Breast milk is better because it is more nutritious
122
Importance of breast milk
Contains all of the essential nutrients for babies
Contains antibodies that protect babies from diseases
Relationship between mother and baby become closer
Important for the emotional development of the baby
Better digestion
123
What’s infertility/sterility
Inability to produce offsprings
124
factors of sterility in males
testes cannot produce sperms
low sperm count
low quality sperms
impotent
125
factors of sterility in females
ovaries cannot produce ovum
blockage in the Fallopian tubes
abnormal uterus
tumour in the uterus
126
factors of sterility in both males and females
hormone imbalance
defective reproductive organs/organs infected with disease
health problems like diabetes
127
methods to overcome sterility
hormone treatment
surgery
in vitro fertilisation (IVF)
128
what is IVF/in vitro fertilisation
takes out the ovum to be fertilised with the sperm outside the body in a glass dish
the embryo is then put inside the uterus
129
what is contraception
the act of preventing pregnancy
130
methods of contraception
contraceptive pills
implants
condom
intrauterine contraceptive device (IUCD)
vasectomy
ligation
131
how does contraceptive pills work
prevents ovulation
132
how does implants work
secretes a hormone that prevents the ovary from producing ovum
the implant is inserted to the skin below the arm
133
how does condoms work
worn over the penis before copulation to prevent the sperm from entering the vagina during ejaculation
134
how does intrauterine contraceptive devices (IUCD) work
inserted inside the uterus to prevent implantation
135
how does vasectomy work
surgery that cuts the sperm duct and the ends are tied
prevents the sperms from being transported to the urethra
136
how does ligation work
surgery that cuts the Fallopian tube and the ends are tied
prevents the ovum from meeting the sperms
137
what is stamen
male reproductive organ of a flower
138
what is pistil
female reproductive organ of a flower
139
parts of the stamen
anther
filament
140
parts of the pistil
stigma
style
ovary
ovule
141
petal
colourful to attract insects and animals
142
sepal
green
protects the flower during bud stage
143
anther
produces pollen grains
144
filament
supports the anther
145
stigma
place where pollen lands
sticky so that pollen can stick onto it
146
style
tube through which pollen is delivered to the ovary
147
ovary (flower)
contains ovules
148
ovule
turns into seeds after fertilisation
149
types of flower
**unisexual**
- male
only has stamen
- female
only has pistil
**bisexual**
has both stamen and pistil
150
examples of unisexual flowers
corn flower
papaya flower
151
types of pollination
self-pollination
cross-pollination
152
whats self-pollination
pollen grains are transferred to the stigma of another flower on the same plant
pollen grains are transferred to the stigma of the same flower
153
whats cross-pollination
pollen grains are transferred to the stigma of another flower on a different plant of the same species
154
pollinating agents
animals & insects
wind
155
how do animals and insects pollinate
pollen grains stick on its body
when it goes to another flower, the pollen grains will stick onto the stigma of that flower
156
characteristics of animal/insect-pollinated flowers
big and colourful petals
have nectar
smell nice
rough and sticky pollen grains
157
how does wind pollinate
light pollen grains are blown by the wind and reaches the stigma of another flower
158
characteristics of wind-pollinated flowers
white/pale petals
long and furry stigma
long filament and style
many small, smooth, light pollen grains
159
what does cross-pollination do
combines genetic materials from two parent plants of the same species
160
advantages of cross-pollination
healthier plants which can adapt better to changes in the environment
new varieties of plants
good quality seeds
new plants that are more resistant to pests and diseases
161
examples of innovation of cross-pollination in agriculture
**palm oil**
hybrid plant: Tenera
**papaya**
hybrid plant: Eksotika
**corn**
hybrid plant: Masmadu
**paddy**
hybrid plant: Malinja
162
parent plants of Tenera
Pisifera and Dura
163
parent plants of Eksotika
Subang 6 and Sunrise Solo
164
parent plants of Masmadu
sweet corns from Taiwan and Mexico
165
parent plants of Malinja
Siam-29 and Pebifun
166
characteristics of Tenera
more fruits and flesh, thinner shell
167
characteristics of Eksotika
sweeter fruits, more flesh
168
characteristics of Masmadu
sweeter and bigger fruits
higher resistance towards diseases and drought
169
characteristics of Malinja
more harvest
ripe faster
170
plant fertilisation process
1 pollen fall onto stigma
2 pollen tube carrying male gamete grows towards the ovary
3 after the pollen tube penetrates the ovule, the male gamete fuses with the female gamete (fertilisation)
171
types of seeds
monocotyledonous
dicotyledonous
172
structure of monocotyledonous seed
testa
micropyle
hilum
plumule
radicle
cotyledon
173
structure of dicotyledonous seed
seed coat
radicle
endosperm
cotyledon
plumule
174
testa
protects the seed
175
hilum
place where the seed sticks to the fruit
176
micropyle
small hole to allow air and water to enter the seed
177
plumule
part of the embryo which develops into a new shoot
178
radicle
part of the embryo which develops into the root
179
cotyledon/endosperm
stores and provides food for the seed
180
germination process
the testa bursts and the radicle starts to appear and grow downwards into the soil to form root. The plumule grows upwards to form a new shoot.
181
epigeal germination
the cotyledon is carried out of the soil during germination
182
hypogeal germination
the cotyledon remains in the soil during germination
183
conditions required for seed germination
water
air
suitable temperature
184
whats matter
a substance that has mass and occupies space
185
physical property
properties that can be identified by using our five senses or measuring tools
186
chemical property
properties of a substance that become evident when it changes into a new substance
187
solubility
ability of a substance to dissolve in a given amount of solvent to form a solution
188
solute
thing the solvent dissolves into
water
189
solvent
thing that dissolves into solute
milo powder
190
solution
solvent + solute
milo
191
solid
small space between particles
very close particle arrangement
particles vibrate in a fixed position
192
liquid
moderate space between particles
close particle arrangement
move freely and collide with one another
193
gas
large space between particles
very loose particle arrangement
move randomly and collide with one another
194
rate of diffusion in solid, liquid and gas
solid: low
liquid: higher than solid
gas: highest
195
Function of fiber for pregnant women
Prevents constipation
196
Examples of food with iron
Liver, red meat, fish
197
Function of iron for pregnant women
Formation of haemoglobin to prevent anaemia
198
Examples of food with vitamin C
Citrus fruits, guava and tomatoes
199
Function of vitamin C for pregnant women
Skin health of foetus and mother
Prevent bleeding gums
200
Food that contains folic acid
Broccoli
Spinach
Groundnuts
201
Function of folic acid for pregnant women
Foetus nervous system development
202
Function of protein for pregnant women
Important for the growth of new cells for the foetus
203
Function of calcium and phosphorus for pregnant women
Healthy formation of foetus bones
Protect the bones and teeth of the mother
204
Nutrients a pregnant woman needs
Fiber
Iron
Carbohydrates and fat
Vitamin C
Folic acid
Protein
Calcium and phosphorus
205
Melting point of water
0degrees
206
Boiling point of water
100degrees
207
Melting point of alcohol
-117
208
Boiling point of alcohol
78
209
Melting point of copper
1085
210
Boiling point of copper
2562
211
Melting point of oxygen
-218
212
Boiling point of oxygen
-183
213
Does the temperature remain constant during boiling, freezing and melting?
Yes, because the energy/heat is used up for the conversion of state
214
Does the mass remain constant after boiling or freezing? (or any other process)
Yes because the quantity of particles does not change
215
How can you see atoms
Using electron microscopes
216
Structure of atom
Nucleus: proton, neutron
Electron
217
Proton
Particle with positive charge
218
Electron
Particle with negative charge
219
Neutron
Neutral particle with no charge
220
How many protons and electrons are there in an atom
Equal amount
Thus, atoms are neutral
221
Molecules
Particles made up of two or more atoms
222
Elements
Simplest form of substance
Only one type of atom
223
Compounds
Two or more elements combined chemically
224
Differences between metals and non metals
Appearance
Ductility
Malleability
Tensile strength
Electrical conductivity
Heat conductivity
Density
Melting point and boiling point
225
Appearance of metals vs non metals
Metals: shiny
Non metals: dull
226
Ductility of metals vs non metals
Metals: ductile
Non metals: brittle
227
Malleability of metals vs non metals
Metals: malleable
Non metals: non-malleable
228
Tensile strength of metals vs non metals
Metals: high
Non metals: low (break easily)
229
Electrical conductivity of metals vs non metals
Metals: good
Non metals: poor (except carbon)
230
Heat conductivity of metals vs non metals
Metals: good
Non metals: poor
231
Density of metals vs non metals
Metals: high
Non metals: low
232
Melting point and boiling point of metals vs non metals
Metals: high
Non metals: low
233
Mixtures
Consists of two or more elements or compounds mixed physically
234
Methods to separate mixtures
Filtration
Distillation
Separation by using magnet
Sedimentation
Floatation
Chromatography
Sieving
235
How to seperate paper clips and glass fragments
Using magnet
236
How to seperate water and ethanol
distillation
237
How to seperate three types of water-soluble ink
chromatography
238
How to seperate soil and water
sedimentation
239
How to seperate oil and water
floatation
240
How to seperate coffee powder and water
filtration
241
magnesium + oxygen --->
magnesium oxide
242
lithium + water --->
lithium hydroxide + hydrogen gas
243
iron + sulphur --->
iron sulphide
244
how to get iron sulphide
Iron and sulphur powder will form iron sulphide when heated
245
Electrolysis
a chemical decomposition of a compound to its elements by passing an electrical current through the compound
246
Physical change
does not form a new substance
247
Chemical change
forms a new substance that is different from the original substances.
248
composition of air
78% nitrogen
21% oxygen
0.97% inert gases and other substances
0.03% carbon dioxide
249
inert gases
Helium
Argon
Neon
Xenon
Krypton
250
Carbon cycle definition
Cycle that maintains the content of carbon dioxide in the air by continuously taking carbon dioxide from the air and returning it to the air
251
Carbon cycle
1. Green plants absorb carbon dioxide through photosynthesis
2. Animals eat the plants, obtain carbon from the plants
3. Plants and animals decompose when they die
4. Decomposition caused by bacteria and fungi in the soil releases carbon dioxide
5. Burning of fossil fuels that contain carbon releases carbon dioxide
6. Plants and animals release carbon dioxide during respiration
7. Decomposition, combustion, respiration are balanced by photosynthesis
252
Carbon cycle
1. Green plants absorb carbon dioxide through photosynthesis
2. Animals eat the plants, obtain carbon from the plants
3. Plants and animals decompose when they die
4. Decomposition caused by bacteria and fungi in the soil releases carbon dioxide
5. Burning of fossil fuels that contain carbon releases carbon dioxide
6. Plants and animals release carbon dioxide during respiration
7. Decomposition, combustion, respiration are balanced by photosynthesis
253
Definition of oxygen cycle
A continuous cycle that takes oxygen from the air and returns it to the air
254
Oxygen cycle
Oxygen needed in respiration, rusting, combustion and decomposition is obtained from photosynthesis
255
Ways to prevent interferences in the oxygen and carbon cycle
Prohibit illegal logging
Avoid using excessive pesticides
Reforestation
Prevent excessive release of smoke from vehicles
Do not burn forests
256
Conditions needed for combustion
Oxygen
Fuel
Heat
257
What type of fire extinguishers can put out solid fire
Water
Dry powder
258
What type of fire extinguishers can put out liquid fire
Foam
Dry powder
Carbon dioxide
259
What type of fire extinguishers can put out gas fire
Foam
Dry powder
Carbon dioxide
260
What type of fire extinguisher can put out metal fire
Dry powder
Dry sand
261
Safety measures to prevent fire
Keep matches and lighters in a safe place
Keep flammable substances away from fire
Always be aware of electrical appliances
Do not plug in too many electrical appliances in one electrical source
Install smoke alarm and fire detectors
Do not throw away cigarette butts when they are still burning
262
How is the periodic table arranged
By increasing proton number
263
How to get atomic mass/nucleon
Proton/electron + neutron
264
What can smoke and dust cause
Breathing problems
Stain buildings
Haze
Decrease sunlight, less photosynthesis
265
What can sulphur dioxide cause
Respiratory problems
Acid rain
266
What can carbon monoxide cause
Headache
Mental retardation
Death
267
What can asbestos particles cause
Lung cancer
268
What can CFC chlorofluorocarbons cause
Thins ozone layer
269
What can lead particles cause
Intellectual disability among children and babies
270
What can acid rain cause
Corrodes concrete and limestone buildings
Speeds up iron rusting
Soil becomes acidic and not fertile
Water becomes acidic and not suitable for aquatic life
271
What can nitrogen dioxide and sulphur dioxide cause
Acid rain
272
What type of converter on vehicle is more sustainable
Catalytic converter
273
What type of refrigerator is more sustainable
HCFC hydrofluorocarbon refrigerator
274
Types of mirrors
Plane mirror
Convex mirror
Concave mirror
275
Real image vs virtual image
Real image
Image that is formed on a screen
Virtual image
Image that cannot be formed on a screen
276
characteristics of plane mirror
1) Virtual
2) laterally inverted
3) distance between the object and the mirror is the
same as the distance between the image and the
mirror
4) upright
277
characteristics of concave mirror
1) Virtual
2) Upright
3) Magnified
4) Laterally inverted
278
characteristics of convex mirror
1) Virtual
2) Upright
3) Laterally inverted
4) Diminished (smaller)
279
uses of plane mirrors
Help dancers to correct their movements
To make rooms look more spacious
280
uses of concave mirrors
magnifies the image to make it easier to apply makeup
used by a dentist to make the patient's teeth look bigger
281
uses of convex mirrors
Used as a safety feature at dangerous corner of a road
helps the shopkeeper to see every corner to prevent theft
282
whats periscope
Periscope is an instrument used in submarines to observe the sea surface.
the sea surface is hit through the top mirror and is reflected. The light is then reflected again at the second mirror, right into the eye of the observer in the submarine
283
whats kaleidoscope
a toy that can create patterns using plane mirrors
These patterns are obtained due to the repeated reflection of the image of the objects inside the kaleidoscope. Therefore, the number of images seen is more than the number of objects.
284
speed of light
3.0x108 ms-1
285
how does light travel
in a straight line
286
How are shadows formed?
1. Sunlight travels in straight lines
2. sunlight cannot pass through opaque objects
3. When light is blocked, shadow is formed.
287
is the length of shadow always the same
the length of shadow will be different based on the position of the sun
shadow will become short in the afternoon and long in the evening
288
application of shadow
sundial
shadow play
289
reflection of light
light bounces off the surface of an object
290
law of reflection
The angle of incident, i is equal to the angle of reflection, r
291
refraction of light
bending of a light ray when it enters a medium of different density
292
where does light bend towards when it travels from a less dense medium to a more dense medium
bends towards normal line
293
where does light bend towards when it travels from a more dense medium to a less dense medium
bends away from normal line
294
is light refracted when it hits the surface at 90 degrees
no!!
295
dispersion of light
separation of white light into its components of colours using prism
296
characters of light?!1
1. White light – consists of 7 colours
2. Different colour, different speed
3. Higher speed, less refracted
297
what colour has the highest speed and least refracted
red
298
what colour has the lowest speed and least refracted
violet
299
how is rainbow formed
Sunlight entering droplets of rain water will be refracted and dispersed into the seven colours of light.
The seven colours of light are reflected and refracted out of the rain water droplets
