This question is about oxygen and substances containing oxygen - AQA - GCSE Chemistry - Question 3 - 2017 - Paper 1
Question 3
This question is about oxygen and substances containing oxygen.
3 (a) (i) Complete Figure 4 to show the arrangement of the outer shell electrons in an oxygen molecu... show full transcript
Worked Solution & Example Answer:This question is about oxygen and substances containing oxygen - AQA - GCSE Chemistry - Question 3 - 2017 - Paper 1
Step 1
Complete Figure 4 to show the arrangement of the outer shell electrons in an oxygen molecule.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To represent the arrangement, place 2 dots (•) in one circle and 2 crosses (×) in the other circle, indicating the shared pairs of outer shell electrons, resulting in a double bond.
Step 2
Name the type of bonding in an oxygen molecule.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The type of bonding in an oxygen molecule is covalent bonding, where electrons are shared between the two oxygen atoms.
Step 3
Explain why oxygen has a low boiling point.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Oxygen has a low boiling point due to weak intermolecular forces between the molecules. The low energy required to overcome these forces leads to a low boiling point.
Step 4
Balance the equation for the reaction.
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The balanced equation for the reaction is:
ightarrow 2 ext{MgO}$$
Step 5
Describe what happens, in terms of electrons, when magnesium atoms react with oxygen atoms to produce magnesium oxide.
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
When magnesium reacts with oxygen, magnesium atoms lose 2 electrons to become Mg²⁺ ions, while oxygen atoms gain 2 electrons to form O²⁻ ions. This transfer of electrons leads to the formation of ionic bonds between the oppositely charged ions.
Step 6
What are nanoparticles?
97%
121 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Nanoparticles are particles that are usually in the size range of 1-100 nm. They contain a few hundred atoms or ions and have a high surface area to volume ratio.
Step 7
Explain, in terms of structure and bonding, why silicon dioxide is used to line furnaces.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Silicon dioxide has a high melting point because it has a giant covalent structure, where all atoms are linked by strong covalent bonds. A significant amount of energy is required to break these bonds, enabling it to withstand high temperatures without melting.
