Tests are used to identify ions in three salts X, Y and Z - Edexcel - GCSE Chemistry - Question 2 - 2015 - Paper 1
Question 2
Tests are used to identify ions in three salts X, Y and Z.
(a) (i) In a flame test salt X gives a yellow flame.
What is the metal ion in salt X?
Put a cross (X) in ... show full transcript
Worked Solution & Example Answer:Tests are used to identify ions in three salts X, Y and Z - Edexcel - GCSE Chemistry - Question 2 - 2015 - Paper 1
Step 1
What is the metal ion in salt X?
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 metal ion in salt X, which gives a yellow flame during the flame test, is sodium (Na⁺).
Step 2
Describe how a flame test is carried out on a solid.
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
To carry out a flame test on a solid, follow these steps:
Clean the platinum wire loop by dipping it in hydrochloric acid and then placing it in a flame until it no longer colors the flame.
Allow the loop to cool before dipping it into the solid sample.
Place the loop with the sample into the hottest part of the flame and observe the color produced. Note the flame color produced to identify the metal ion present.
Step 3
Describe what you would see when the barium chloride solution is added.
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
When barium chloride solution is added to the mixture containing sulfate ions, a white precipitate of barium sulfate (BaSO₄) is formed, indicating the presence of sulfate ions.
Step 4
Describe what is seen when sodium hydroxide solution is added to a solution of Z.
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
When sodium hydroxide solution is added to the solution containing iron(III) ions, a reddish-brown precipitate of iron(III) hydroxide (Fe(OH)₃) is observed.
