Measure about 1cm of sodium carbonate Free Essay Example

1. Measure about 1cm of sodium carbonate in a test tube and add the same amount of dilute hydrochloric acid.

2. Using a clean pipette, withdraw a sample of gas and bubble it through some lime – water in a clean test tube. If there is a white precipitate then the gas produced was carbon dioxide.

3. Dispose of the contents down the sink using plenty of water.

2) REACTION BETWEEN A METAL AND A DILUTE ACID

1. Take a few pieces of magnesium ribbon, place in a test tube and add approximately 2cm of dilute hydrochloric acid.

2. Hold your thumb over the top of the test tube until you can feel the pressure of the gas pushing against your thumb. Remove you’re thumb and hold a lighted splint to the mouth of the test tube.

A small explosion confirms that the gas produced is Hydrogen.

3. When there is no solid left dispose of solution in a sink with plenty of running water.

3) REACTION BETWEEN A CHLORIDE AND CONCENTRATED SULPHURIC ACID.

1. Measure a small amount of sodium chloride in a test tube add a few drops of concentrated sulphuric acid. Do this in the fume cupboard and make sure you are wearing gloves.

2. Note the effervescence (bubbling) as hydrogen is produced. Blow across the mouth of the test tube and note the misty fumes.

3. Test the gas with moist universal indicator paper. Then dip a dry, clean glass rod into concentrated ammonia solution in the fume cupboard and hold the rod over the mouth of the test tube. Note the white smoke.

4. Put the test tubes in a rack and leave in the fume cupboard.

4) REACTION BETWEEN AN AMMONIUM SALT AND SODIUM HYDROXIDE SOLUTION

1. Measure a small amount of ammonium chloride in a test tube and add approximately the same amount of dilute sodium hydroxide solution. Then warm the tube gently over a Bunsen burner (blue flame).

2. Test the gas with moist universal indicator paper. Next smell the gas with caution. An alkaline gas with this smell is Ammonia.

3. Dispose of the contents down the sink with plenty of running water.

5) REACTION BETWEEN MANGANESE (IV) AND CONCENTRATED HYDROCHLORIC ACID.

1. Working in the fume cupboard, measure a small amount of manganese (iv) oxide in a test tube and add an equal amount of concentrated hydrochloric acid. If no reaction in the cold, remove from the fume cupboard and heat gently on a Bunsen burner.

2. As soon as you see bubbles of gas take the tube back to the fume cupboard and hold some moist blue litmus paper at the mouth of the test tube. Note the litmus paper first turns red then bleached. This is characteristic of a chlorine gas.

3. Leave the test tube in a rack in the fume cupboard.

6) ACTION OF HEAT ON POTASSIUM NITRATE

1. Measure approximately 2cm of potassium nitrate crystals into a semi micro tube. Heat gently until the solid has melted then heat more strongly until the liquid appears to boil.

2. Put a glowing splint inside the mouth of the test tube. The splint should relight showing that Oxygen has been produced.

3. Leave the test tube to cool and then add water from the tap.

7) ACTION OF HEAT ON LEAD (II) NITRATE

1. Measure approximately 1 cm of lead (II) nitrate in a test tube and heat. Be careful as the crystals may spit out of the test tube.

2. Two gases are produced. Confirm on of them is oxygen by holding a glowing splint inside the mouth of the test tube. If it relights, oxygen has been produced.

3. The other is brown. Confirm that it is acidic (nitrogen oxide) by holding a piece of moist universal indicator paper.

4. Put the test tube back in the fume cupboard in a test tube rack.

8) REACTION BETWEEN A SULPHITE AND A DILUTE ACID

1. Measure approximately 1 cm if sodium sulphite in a test tube and add approximately the same amount of dilute hydrochloric acid. Warm the test tube.

2. Hold some universal indicator paper over the mouth of the test tube. It should turn red. Put two drops of potassium dichromate solution onto a strip of filter paper as well as a drop of dilute sulphuric acid. Hold the paper over the mouth of the tube. Note that the orange potassium dichromate turns green.

3. Put the test tube in a rack in the fume cupboard.

OBSERVATIONS

1) Reactants: Sodium Carbonate – white crystals

Hydrochloric acid – colourless solution.

There was some effervescence and a gas which turned Lime water cloudy was produced. The gas was therefore carbon dioxide. A colourless solution remained in the test tube.

Sodium carbonate = Na2CO3

Hydrochloric acid = HCl

Na2CO3 + HCl ? CO2 + other products

Sodium chloride = NaCl

Water = H2O

Na2CO3 + HCl ? CO2 + NaCl + H20

Na2CO3 + HCl ? CO2 + 2NaCl + H2O

Na2CO3 + 2HCl ? CO2 + 2NaCl +H2O

Na2CO3 (s) + 2HCl (aq) ? CO2 (g) + 2NaCl (aq) + H2O

2) REACTION BETWEEN A REACTIVE METAL AND A DILUTE ACID.

Reaction between magnesium and Hydrochloric acid.

REACTANTS: Magnesium – thin strips of magnesium ribbon, Hydrochloric acid – Colourless solution

Vigorous effervescence, there was also a small explosion which occurred confirming that the gas produced was Hydrogen.

Magnesium = Mg

Hydrochloric acid = HCl

Mg + HCl ? H2 + MgCl2

Mg (mg) + 2HCl (aq) ? H2 (g) + MgCl2 (s)

Reaction which caused the small explosion.

H2 + O2 ? H2O

H2 + O2 ? 2H20

2H2 (g) +O2 (g) ? 2H2O (aq)

3) REACTION BETWEEN A CHLORIDE AND A CONCENTRATED SULPHURIC ACID

Reaction between Sodium Chloride and concentrated Sulphuric Acid.

Reactants: Sodium Chloride – White crystals/powder

Hydrochloric acid – colourless solution

Sodium Chloride = NaCl

sulphuric acid = H2SO4

Slight effervescence, misty fumes when blown across the top, PH1 acidic, white smoke produced, confirming Hydrogen Chloride was produced.

NaCl +H2SO4 ? HCl + Na2SO4

2NaCl (s) + H2SO4 (aq) ? 2HCl (aq) + Na2SO4 (s)

Reaction between Hydrogen Chloride and ammonia.

Hydrogen Chloride (HCl) = Colourless Gas

Ammonia (NH3) = colourless gas with strong pungent odour

HCl (g) + NH3 (g) ? NH4Cl (s)

4) REACTION BETWEEN AN AMMONIUM SALT AND SODIUM HYDROXIDE SOLUTION.

Reactants: Sodium Hydroxide ( NaOH) = White solid

Ammonium Chloride (Nh4Cl) = White solid

Universal indicator paper turned blue, therefore the gas is alkaline. Very characteristic smell, suggesting that the gas produced is ammonia.

NH4Cl (s) + NaOH (s) ? Nh3 (g) + NaCl (s) + H20 (aq)

5) REACTION BETWEEN MANGANESE (IV) OXIDE AND CONCENTRATED HYDROCHLORIC ACID.

Reactants: Manganese (IV) oxide (MnO2) = black solid

Hydrochloric acid (HCl) = colourless solution

Slight effervescence when cold but disappeared when warmed. Black solution turned the litmus paper red then bleached, suggesting chlorine was present. Black solution left in test tube.

MnO2 + HCl ? Cl2 + MnCl2 +H2O

MnO2 (s)+ 4HCl (aq) ? Cl2 (g) + MnCl2 (s) +2H2O (aq)

6) ACTION OF HEAT ON POTASSIUM NITRATE

Reactants: Potassium Nitrate (KNO3) = White solid

Heat

Solid melted and liquid appeared to boil. Glowing splint added and the splint relit showing that Oxygen was present.

KNO3 ? o2 + KNO2

2KNO3 (s) ? O2 (g) + 2KNO2 (s)

7) ACTION OF HEAT ON LEAD (II) NITRATE.

Reactants: Lead (II) Nitrate (Pb (NO3)2 = White odourless solid

Heat

Oxygen produced as glowing splint relit. Second gas produced was acidic Nitrogen Dioxide.

Pb(NO3)2 ? O2 + NO2 + PbO

2Pb(NO3)2 (s)? 2PbO + 4NO2 (g) + O2 (g)

8) REACTION BETWEEN A SULPHITE AND A DILUTE ACID.

Reactants: Sodium Sulphite (Na2SO3) = White Grains

Hydrochloric Acid (HCl) = Colourless solution

When I added potassium dichromate solution and dilute sulphuric acid to the universal indicator paper it turned yellow/ orange. When put over the mouth of the test tube the universal indicator paper turned green.

Na2SO3 + HCl ? SO2 + H20 +NaCl

Na2SO3 (s) + 2HCl (aq) ? SO2 (g) + H20 (aq) + 2NaCl (s)