C12 - Chemical Analysis 2️⃣✅ Flashcards
What is the test for hydrogen?
The test for hydrogen uses a burning splint held at the open end of a test tube of the gas
What is the positive & negative result for hydrogen?
Postitive = squeaky pop sound
Negative = no noise/ sound
What is the test for oxygen?
The test for oxygen uses a glowing splint inserted into a test tube of of gas
What is the positive & negative result for oxygen?
Positive = splint relighting when in tube (in oxygen)
Negative = splint doesnt relight
What is the test for carbon dixoide?
The test for carbon dioxide uses an aqueous solution of calcium hydroxide (lime water).
What is the positive & negative result for carbon dioxide?
Positive = When bubbled through limewater via delivery tube limewater turns milky/ cloudy
Negative = When bubbled through limewater via delivery tube limewater remains clear
What is the test for chlorine?
The test for chlorine uses litmus paper
What is the positive & negative result for chlorine?
Positive = litmus paper turns from blue to red (as chlorine gas is acidic) and then bleaches to white
Negative = litmus paper remains normal
What ions does the flame test identify?
Some positive metal ions such as Lithium, Sodium, Potassium, Calcium & Copper ions
What ions would be present if the flame colour is crimson?
Lithium ions
What ions would be present if the flame colour is yellow?
Sodium ions
What ions would be present if the flame colour is lilac?
Potassium ions
What ions would be present if the flame colour is orange-red?
Calcium ions
What ions would be present if the flame colour is green?
Copper ions
What is a precipitate?
A solid formed by a change in a solution, often due to a chemical reaction or change in temperature
What is the metal ion precipitate test used to identify?
Some positive metal ions such as Aluminium, Calcium, Magnesium, Copper (II), Iron (II) & Iron (III) ions
What ions are present if the precipitate turns white?
metal precipitate test
Aluminium, Calcium or Magnesium ions
What ions are present if the precipitate turns blue?
Copper (II) ions
What ions are present if the precipitate turns green?
Iron (II) ions
What ions are present if the precipitate turns brown?
Iron (III) ions
What 2 tests are used to indentify cations?
- Flame tests
- Metal ion precipitate test
What is the carbonate test?
When a carbonate is reacted with a dilute acid to form carbon dioxide gas to then be tested to identify the solution as a carbonate
What is the positive & negative result for the carbonate test?
Positive - solution has reacted with dilute acid and produced carbon dioxide gas which has subsequently caused the limewater to go cloudy
Negative - limewater remains clear
What is the halide test?
When halide ions in a solution produce coloured precipitates representative of halide ions when reacted with silver nitrate solution in the presence of dilute nitric acid.
What ions does the halide test identify?
Chloride, Bromide & Iodide ions