Map of the Early Jurassic age 200 million years ago Here is a map of the world in the mid-Jurassic period (about 200 million years ago). Before this the world's land mass was one super-continent known as Pangaea. 200 million years ago Pangaea started to break apart with the sea working its way into the rift valleys formed between North America and Africa.

Late Jurassic age 150 million years ago During the Jurassic period, Pangaea began to break-up into two smaller super-continents: Laurasia ( North America, Europe, and Asia), and Gondwanaland (combining South America, Africa, India, Australia and Antarctica).

The Jurassic world was warmer than that of today and there seems to have been no glaciation or ice caps at the poles

Large dinosaurs  roamed forests of large conifer trees during the Jurassic Period.

Dinosaur Footprint

New Coral Seas Sunlight shined brightly on the waters surface and shafts of light penetrated to the sea floor. Tall crinoids caught particles of food with their branch-like tentacles, as Cryptoclidus swooped into the scene over a dense coral reef that spread out across the seabed. (Late Jurassic).

These were shallow tropical waters with a seabed rich with life These were shallow tropical waters with a seabed rich with life.  The shells of these sea creatures were composed of calcium carbonate. When they died the shell accumulated at the bottom of the sea to form the limestone, which today we know as the Jura.

Limestone Fossils

The Jura Today

Experiment One: Heating Limestone or Chalk 1. Put a stick of chalk into the holder and heat it in a roaring Bunsen flame. Continue heating for 10 minutes until at least some of the limestone chip glows brightly. Leave it to cool, meanwhile move on to experiment four. The calcium carbonate is broken up (decomposed) by the heat. A gas (which you cannot see) is given off. Page 2

Making Limelight In the olden days the bright light for spotlights were made by heating lime. Calcium Oxide Screw for rotating and raising the Calcium oxide Hydrogen Oxygen

Experiment 1 What do you think the gas will be? ______________ Carbon Dioxide What do you think the gas will be? ______________ The new substance glows with a bright light when heated. Large blocks of limestone were, many years ago, heated in this way to provide a bright light (limelight) for theatres. What is the solid left behind when calcium carbonate decomposes: ______________ Calcium oxide Page 2

Experiment 1 Equation Write word and symbol equations for the reaction when limestone is heated.   WORD: CALCIUM CARBONATE -----> ________________ + ________________ SYMBOL: CaCO3 -----> ________________ + ________________ Carbon Dioxide Calcium oxide CO2 CaO Page 2

Experiment 2 « Thirsty Lime » When the solid from experiment one is cool put it into a small beaker with a pair of tongs. DO NOT TOUCH IT! Carefully, using a dropping pipette, add three or four drops of water to the solid. Observe what happens and feel the bottom of the watch glass. The solid looks lively! It is commonly called QUICKLIME. Record ALL your observations:- Page 3

SLAKED LIME QUICKLIME reacts very violently with water. The new white sold is SLAKED LIME, chemical name, Calcium hydroxide. + -> CaO + H2O -> Ca(OH)2 SAVE the calcium hydroxide you have made for the next experiment . C ALCIUM OXIDE CALCIUM HYDROXIDE WATER Page 3

Expt. 3 Making Limewater Take the calcium hydroxide (slaked lime) you made earlier. Add a quarter spatula measure of it to a boiling tube and half fill it with de-ionised water. Page 5

Expt. 3 Making Limewater Stir with a glass rod to dissolve some of the solid. Page 5

Filtering Filter the mixture into a conical flask. You have now made a solution of calcium hydroxide. Ca(OH)2 (s) + H2O (l) -> Ca(OH)2 (aq) Draw a neat labelled diagram of the filtering apparatus. Use a pencil and ruler. Solid calcium hydroxide Calcium hydroxide solution Page 5

Expt. 4 The carbon dioxide test Blow gentley and make sure the straw is half way in the water. Complete the word and symbol equations: CALCIUM + CARBON -------> + WATER HYDROXIDE DIOXIDE ____________ SYMBOLS: CALCIUM CARBONATE straw End of straw Ca(OH)2 + CO2  CaCO3 + H2O You have now made a suspension of Calcium Carbonate or limestone. IMPORTANT keep this solution for Experiment 7 Page 5

Expt. 5 Acid & Slakedlime Add about 1cm depth of hydrochloric acid to a test-tube and two drops of universal indicator. Add a small spatula measure of the slaked lime to the test-tube and stir it with a glass rod. Describe what happens to the solid and the universal indicator. Page 3

Adding Lime to Acid Soil Page 3

Experiment 5 Equation +  + Ca(OH)2 + ____HCl  CaCl2 + ________ C ALCIUM HYDROXIDE HYDROCHLORIC ACID CALCIUM CHLORIDE WATER 2 2H2O Page 3

Experiment Six: Limestone and Acid. Put a piece of limestone into a test tube and add about 5cm3 of dilute hydrochloric acid. A gas is given off, what do you think it will be? ______________________ Carry out a chemical test for this gas. Describe the result and draw a diagram. Page 4

Draw a neat labelled diagram with a pencil and ruler of this experiment. Limewater Page 4

Experiment 6 Equation +  + + CaCO3 + ____ HCl  CaCl2 + ________ + CO2 C ALCIUM CARBONATE HYDROCHLORIC ACID CALCIUM CHLORIDE CARBON DIOXIDE WATER 2 H2O Page 4

Experiment 7 LIMESTONE CAVES In experiment 4 you made a suspension of limestone. The aim of this experiment is to find out what happens to the suspension of limestone when you blow excess carbon dioxide into it. Page 6

Limestone Cave Experiment 7 Continue blowing through the straw into the solution until another change takes place. Describe what happens. Page 6

Limestone Cave Experiment 7 CALCIUM CARBON CALCIUM CARBONATE + DIOXIDE + _______  HYDROGENCARBONATE   CaCO3(s) + ____ + H2O  Ca(HCO3)2(aq) IMPORTANT KEEP THE CLEAR SOLUTION FOR THE NEXT EXPERIMENT. Page 6

Underground Rivers

De L'Allondon est une rivière de l'Ain en France

Jura

Experiment 8 STALACTITES AND STALAGMITES Page 6

Making Calcium Carbonate Again If the solution from experiment seven does not become clear when passing more carbon dioxide through it, filter it again into another clean test-tube. Heat the clear solution. What do you see? Use the equation below to explain what happened. CALCIUM -----> CALCIUM CARBON WATER HYDROGENCARBONATE CARBONATE DIOXIDE + +

Summary Copy out the sentences and equations (page 7) onto the diagram in the appropriate place. Rain drops dissolve carbon dioxide to make a weak acid. H2O(s) + CO2(g) ---------> H2CO3(aq) As rain percolates through calcium carbonate rock which reacts with the weak acid and forms a soluble salt. H2CO3(aq) + CaCO3(s) --------> Ca(HCO3)2(aq) The calcium hydrogen carbonate solution evaporates and leaving calcium carbonate. Ca(HCO3)2(aq)----------> CaCO3(s) + H2O(S) + CO2(g)

What do you call a blind dinosaur?