Testing for Negative Ions and Spectroscopy

Created by: joshd
Created on: 31-03-14 20:12

How can you test to see if a gas is carbon dioxide? What can you use this test for?

By bubbling it through limewater. If it is carbon dioxide, the limewater turns milky. You can use this to test for carbonate ions (CO320-), since carbonates react with dilute acids to form carbon dioxide.

1 of 11

What is the equation for the carbon dioxide gas experiment?

acid + carbonate = salt + water + carbon dioxide

2 of 11

How can you test for certain ions?

By seeing if a precipitate is formed after the reaction.

3 of 11

How do you test for a sulfate ion? (SO42-) (1)

Add dilute HCl, followed by barium chloride solution, BaCl2

4 of 11

What does a white precipitate of barium sulfate mean? What's the equation? (2)

A white precipitate of barium sulfate means the original compound was sulfate. Ba2+(aq) + SO42- (aq) = BaSO4 (s)

5 of 11

How do you test for chloride ions?

Add dilute nitric acid (HNO3), followed by silver nitrate solution (AgNO3)

6 of 11

What does a chloride give? What's the equation?

A chloride gives a white precipitate of silver chloride. Ag+ (aq) + Cl- (aq) = AgCl (s)

7 of 11

How can elements in a sample be identified? What is this?

Using spectroscopy, where the patterns of light emitted by the elements in a heated sample are analysed.

8 of 11

What does each element present in the sample produce?

A different pattern.

9 of 11

Describe the character of spectroscopy.

It is fast and reliable and it can be used to detect even very small amounts of elements in a sample.

10 of 11

What has spectroscopy also allowed? Give an example.

Scientists to discover new elements. For example, rubidium and caesium were both discovered because they produced patterns of light which had not been seen before.

11 of 11

Other cards in this set

Card 2

Front

What is the equation for the carbon dioxide gas experiment?

Back

acid + carbonate = salt + water + carbon dioxide

Card 3

Front

How can you test for certain ions?

Back

Card 4

Front

How do you test for a sulfate ion? (SO42-) (1)

Back

Card 5

Front

What does a white precipitate of barium sulfate mean? What's the equation? (2)

Back

View more cards

Similar Chemistry resources:

See all Chemistry resources »

See all Testing and analysing substances resources »

Get Revising

Testing for Negative Ions and Spectroscopy