Are all limestones different?
Objectives Children should learn: to use preliminary work to find out whether a possible approach is practicable to describe and evaluate how the work was undertaken and what led to the conclusions that rocks are mixtures of varying composition that the composition of a limestone is related to the process of formation Activities Outcomes Children: Show pupils some examples of different limestone, eg brown limestone; ask them to describe some differences between them, eg appearance, porosity. Explain that they are going to find a way of investigating differences in composition. Establish that limestones are carbonate-rich rocks, but may contain other components. Remind pupils of how carbonates react with acids and help them to plan a way of comparing the carbonate content of two samples, eg by weighing samples before and after reacting with acid, measuring the volume of acid required to completely react with the carbonate. Ask pupils to think about what they are planning to do and perha
