Identifying Ions
Q1.
Burgundy Mixture is a formulation used to kill fungi on grapevines.
It is made by mixing two compounds, A and B.
The ratio by mass of A : B in the mixture is 1 : 8
(a)     Calculate the mass of A needed in a mixture containing 125 g of B.
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Mass of A = ____________________ g
(2)
Scientists test a solution of compound A.
The table shows their results.
 
Test	Result	
Add sodium hydroxide solution	Blue precipitate	
Add dilute hydrochloric acid and barium chloride solution	White precipitate	
(b)     Which two ions are in compound A?
Choose the answers from the box.
 
bromide	chloride	copper	
iron(II)	iron(III)	sulfate	
___________________ ions and ___________________ ions
(2)
(c)     The scientists think that compound B is sodium carbonate.
Describe how the scientists can test a solution of B to see if sodium ions are present.
Give the result of the test if sodium ions are present.
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(2)
(d)     Describe how the scientists can test a solution of B to see if carbonate ions are present.
Give the result of the test if carbonate ions are present.
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(3)
(Total 9 marks)