This question is about elements in group 7, the halogens - Edexcel - GCSE Chemistry Combined Science - Question 4 - 2022 - Paper 1
Question 4
This question is about elements in group 7, the halogens.
(a) Which halogen is a green gas at room temperature and pressure?
A bromine
B chlorine
C fluori... show full transcript
Worked Solution & Example Answer:This question is about elements in group 7, the halogens - Edexcel - GCSE Chemistry Combined Science - Question 4 - 2022 - Paper 1
Step 1
Which halogen is a green gas at room temperature and pressure?
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 green gas at room temperature and pressure is chlorine (B).
Step 2
Write the word equation for this reaction.
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
Iron wool + Chlorine → Iron chloride.
Step 3
Give the name of the halogen in Figure 6 that is the most reactive with iron.
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 most reactive halogen with iron in Figure 6 is chlorine.
Step 4
Calculate the mass of iron and the mass of chlorine in 125 g of iron chloride.
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
To find the mass of iron and chlorine in iron chloride (FeCl₂):
Calculate the mass of iron:
Let the mass of iron be x.
Given that 34.4% of the mass of iron chloride is iron:
x = 34.4 ext{%} imes 125g = 43g
To find the mass of chlorine:
The total mass of chlorine can be found by subtraction:
extmassofchlorine=125g−x=125g−43g=82g
Thus, the mass of iron is 43 g and the mass of chlorine is 82 g.
Step 5
Complete the sentences with the correct words from the box.
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
catalyst
unchanged
The iron chloride speeds up the reaction because it is a catalyst. After the reaction, the mass of iron chloride is unchanged.
