Quiz 1 Ans

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Year 9 Advanced Science
Chemistry Quiz ONE 2015 [25 marks]
ANSWERS Name: MR. HUNG
1. Give 2 similarities between neutron and proton. [2 marks]
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Neutron and proton are found in the nucleus of an atom
Both have a mass of unit 1 – much heavier than electron.
Both contribute to the mass of an atom
These sub-atomic particles cannot leave the atom. (Any TWO)
2. Give 2 differences between proton and electron. [2]
 Proton is found in the middle nucleus and Electron is surrounding
the nucleus.
 Proton has a positive charge and electron has a negative charge
 Proton is much heavier than electron. (Any TWO)
3. How to find the neutron number of an atom? [2]
 Mass number is the sum of Proton number and Neutron number
 So, Neutron number = Mass number – Proton number OR
 The difference between the Mass number and Proton number
4. State the name and find the neutron number of the following elements.[4]
Helium
Fluorine
4-2 = 2 neutrons 19-9 = 10
Lithium
7-3 = 4
Uranium
235 – 92 = 143
Bromine
80-35 = 45
5. What is the electronic configuration of the following element? [3]
Eg. ( 2, 8, 4)
(2, 8, 8)
(2, 8, 3)
(2, 6)
6. What is OCTET rule? Which group and elements have this octet arrangement? [5]
 It states that atoms of main-group elements tend to combine in such a
way that each atom has eight electrons in its valence shell,
 giving it the same electronic configuration as a noble gas.
 elements gain or lose electrons to become ions.
 Helium, Argon and Neon.
7. a) Write an equation for the following reaction during the burning of gas in a Bunsen burner.
The following are the chemicals involved: Oxygen, Carbon Dioxide, Methane, Water. [2]
 Methane + Oxygen --------- Water and Carbon Dioxide
b) What are the other products (energy) formed during this reaction? [2]
 Heat and Light from the flame
8. What are the differences between ANION and CATION? Give an example of each type. [4]
 An ANION is a negative ion formed from Non-metal atom after
gaining electron(s)
 Eg. Chloride ion C1 A CATION is a positive ion formed from Metal atom after losing
electron(s)
 Eg. Sodium ion Na+
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