This question is about metals and metal compounds - AQA - GCSE Chemistry - Question 2 - 2018 - Paper 1
Question 2
This question is about metals and metal compounds.
Iron pyrites is an ionic compound.
Figure 1 shows a structure for iron pyrites.
Determine the formula of iron p... show full transcript
Worked Solution & Example Answer:This question is about metals and metal compounds - AQA - GCSE Chemistry - Question 2 - 2018 - Paper 1
Step 1
Determine the formula of iron pyrites.
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
The formula of iron pyrites is FeS2, where iron (Fe) is combined with sulfur (S) in a 1:2 ratio.
Step 2
Number of protons
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 number of protons in an atom of iron is 26.
Step 3
Number of neutrons
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
The number of neutrons in an atom of iron is calculated by subtracting the atomic number from the mass number:
Number of neutrons = Mass number - Atomic number = 56 - 26 = 30.
Step 4
Number of electrons
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 number of electrons in a neutral atom of iron is equal to the number of protons, which is 26.
Step 5
Give two differences between the properties of iron and sodium.
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
Iron has a higher melting point than sodium, making it suitable for higher temperature applications.
Iron is more dense than sodium, contributing to its strength and durability.
Step 6
Explain why carbon can be used to extract nickel from nickel oxide.
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
Carbon can be used to extract nickel from nickel oxide because it is more reactive than nickel. During the reduction process, carbon displaces nickel from nickel oxide, effectively removing oxygen and allowing nickel to be recovered.
Step 7
Calculate the percentage atom economy for the reaction to produce nickel.
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 calculate the percentage atom economy, we first need the total relative molecular mass of reactants:
Total relative mass of reactants = MNiO+MC=75+12=87.
Then, we calculate the percentage atom economy for producing nickel:
Percentage atom economy = (\frac{M_{Ni}}{\text{Total M}_{\text{reactants}}} \times 100 = \frac{59}{87} \times 100 \approx 67.8% ). The answer is 67.8 to three significant figures.
