C
SMA Kr. IntanPermataHati
Jl. Raya KedungBaruk 112 – 114
Surabaya
Final Examination Semester 2
Subject
Time
Class
Name
Year 2021 – 2022
: SCIENCE BIO-CHEM
: 60 minutes
: VII C
: Cailyn Stephanie Runtukahu
……………………………….
SCORE
INSTRUCTION
-
-
-
ANSWER ALL THE QUESTIONS CORRECTLY
YOU MAY MAKE YOUR OWN ANSWER SHEET, BUT PREFERABLY
ANSWER THE QUESTIONS IN THE SPACE PROVIDED, USING A
DIFFERENT COLOUR OR BOLD YOUR ANSWER.
YOU MAY PRINT THE QUESTION PAPER AND DO IT MANUALLY, BUT
DON’T FORGET TO TAKE PICTURES OF YOUR ANSWER SHEET AND
UPLOAD IT IN GC
DON’T FORGET TO CLICK TURNED IN ONCE YOU ARE DONE.
1
STRUCTURED QUESTIONS (50 POINTS)
1.
Choose one metal from the list below to match its properties. The word can
only be used once.
Silver
steel
a.
b.
c.
d.
e.
f.
aluminium
stainless steel
copper
mercury
Liquid metal at room temperature Mercury
Malleable, shiny use in jewelerries Silver
Ductile, conducts electricity use in electrical wiring Copper
Does not rust easily use in cooking utensils Stainless steel
Heavy strong metal use in bridges Steel
Light weighted metal use to keep food warm Aluminium
(6 points)
2.
Universal indicator is used to
measure the pH of a substance.
In a neutral solution which has a
pH of 7 will turn green , but in a
substance with pH of 13 it will be
Violet in colour. However litmus
is a dye made from living
organism. It is Red in acid and
blue in alkali. When litmus paper changes colour we can say that a
Chemical reaction has taking place.
(5 points)
3.
Give 1 reason why you don’t burn your hand when picking up a metal
saucepan with a wooden handle?
Because wooden handle doesn’t conduct heat energy so it wont burn
your hand when your picking up the saucepen
Suggest what could be done if there is an accident and some acids is spilt
on a bench in a laboratory?
Directly clean it using cloth because some acid is corrosive and if
you use tissue it might burn
(3 points)
4.
Choose the best separating techniques from the words in the box below for
questions a-d
chromatography
magnet
filtration
sieve
evaporation
distillation
2
a. sand in a salt water solution? Filteration (to separate salt from the
mixture)
b. iron filling in mixture of sand, paper bits and pebbles
Magnets for separating iron from mixture
c. copper sulphate crystals and pieces of glass. Sieve
d. different colours from a black ink? Chromatography
( 4 points)
5.
The diagram shows an experiment where zinc metal is added to
hydrochloric acid showed in a sequence of A-C
A
B
C
Complete the statement below
a. Comple the equation in tube A
Zinc + hydrochloric acid Zincloride+ Hydrogen
b. What is the name of the gas given off in this reaction? Hydrogen
c. Explain what is happening in tube B? hydrogen gas burn with a
squeeky pop
d. What is the result in tube C?
Reaction take place because there is the pop sound. When the
hydrogen pops, reacting with oxygen with the air from water.
6.
( 5 points)
Write the following whether it is a physical change or chemical reaction.
3
a.
b.
c.
d.
e.
Leaf turning yellow : Chemical change
Ice cream melting : Physical change
Blasting fireworks : Chemical change
Glass crackling after heating it : Physical change
Frying an egg : Chemical changes
(5 points)
7.
Magnesium ribbon burns in the air
a.
What is the chemical symbol for
magnesium Mg
b.
Mention one other metal and its symbol
Potasium, K
c.
Name the element in the air that reacts
with magnesium when it burns. Oxygen
d.
Name the compound formed when this
element reacts with magnesium . Magnesium
Oxide (MgO)
e. Magnesium also reacts with fluorine. Write the equation and name
the reactant and the product.
Magnesium+Florine magnesium floride+ Water
f. What is one safety precautions you need to take while carrying out
this experiment (burning magnesium ribbon) Wear safety goggles
and don’t look directly at the flame
8.
(6 points)
Give two differences between virus and bacteria
1. Viruses might be smaller than bacteria
2. Bacteria can be healed with antibiotics while virus cant
Make a food chain that includes microorganism as decomposers. You
don’t have to draw pictures – just write the names.
Grass Grasshopper frog snake eagle decomposers
(4 points)
9.
Some bacterias are decomposers. They break down food and change it.
Usually this makes the food unpleasant, but sometimes it changes it to
something that is good to eat like yogurt.
4
Questions
a. Mention one way we can slow down decomposition
Make the temperature lower
b. Beside rotting food mention one other negative effect of bacterias.
Cause dieseas
c. Explain why it is a good idea to wash containers before making
yogurt.
So there is no bacteria in the container
d. Mention one other advantage of microorganism beside being a
decomposer.
Can be use to make antibiotic or medicine
(4 points)
10.
Complete the chemical reactions below
a. Tin
+ hydrochloric acid Tin chloride + hydrogen
b. Magnesium
+ Sulfur Magnesium sulphate + Oxygen
c. Sulphuric acid + lithium hydroxide
d. Hydrochloric acid +
hydroxide+ water
e. Calcium
+ water
f. Zinc
+ Water
g. carbon + oxygen
Lithium sulphate + water
sodium hydroxide sodium
calcium hydroxide + hydrogen
zinc hydroxide
+ Hydrogen
carbon oxide
h. Lithium + Oxygen lithium oxide
5
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