C1.5a Looking at rocks Name
Class
Date
You are going to examine four different samples of rock and record their appearance.
Apparatus hand lens
rock samples
Method A Select a piece of rock. Record its name and its overall appearance. B Examine the rock with the help of a hand lens and record its detailed appearance – include the shape, size and colour of any grains. C Repeat steps A and B with the other samples of rock. Record your results in the tables below. Name of rock: Chalk
Type of rock: Sedimentary
Overall appearance
Detailed appearance
Name of rock: Limestone
Type of rock: Sedimentary
Overall appearance
Detailed appearance
Name of rock: Marble
Type of rock: Metamorphic
Overall appearance
Detailed appearance
Name of rock: Granite Overall appearance Detailed appearance
Š Pearson Education 2010. Edexcel GCSE Science Activity Pack. This document may have been altered from the original.
Type of rock: Igneous
C1.5b A model for crystal size in igneous rocks Name
Class
Date
As molten magma cools, it freezes and starts to form crystals. Like rocks, magma is made of many different minerals, and different minerals have different freezing points. However, most magmas have a freezing point between 700 °C and 1300 °C. Molten magma is so hot that it would be very difficult, in a lab, to study crystals forming in molten magma as it cools. Instead, molten salol can be used to model what happens in molten magma. As it cools, molten salol freezes at 41 °C and forms crystals. You are going to investigate how the rate of cooling affects the size of the crystals formed in molten salol.
Prediction 1
Which will produce the largest crystals – slow cooling or rapid cooling? __________________________________________________________________
Apparatus eye protection 2 × test tubes containing molten salol IRRITANT 2 × beakers hand lens
Health and safety ● ● ●
Wear eye protection Salol is IRRITANT – avoid breathing the vapour Take care with the hot test tubes
Method Read through the method before you start. A Collect two test tubes of molten salol and stand each in its own beaker. B Add cold water to one beaker. The test tube in this beaker will cool more quickly than the other test tube. C Observe the crystals forming as the salol cools down – it may help to use the hand lens.
Recording your results 2
Draw a suitable table for your results. It should include space to record the appearance of the crystals formed in each test tube.
Considering your results/conclusions 3
How easy was it to see the different crystals?
4
Which salol test produced the biggest crystals – the one that cooled quickly in cold water, or the one that cooled slowly in air?
5
What conclusion can you draw about the effect of the rate of cooling on crystal size?
Evaluation 6
Describe how well the molten salol model explains the differences we can see in crystal size in igneous rocks. For example, which part of the model is effective? Does the model have any weaknesses (things it cannot explain)?
© Pearson Education 2010. Edexcel GCSE Science Activity Pack. This document may have been altered from the original.
C1.5c Rock formation jumble Instructions Cut each card out. Sort the cards into three piles – sedimentary, igneous and metamorphic. In each pile, sort the cards into the correct order. Stick the sorted cards into your book, or write down the main steps involved in the formation of each type of rock. E Use the information in the Student Book to write down the main features of each type of rock. A B C D
Rocks are broken into small pieces
Rocks become buried deep underground
Rocks are heated until they melt
Over a very long time, layers are compacted or squashed together to form new rock
Molten rock solidifies and crystals form
Rocks are changed by the action of heat and/or pressure
Molten rock cools
Pieces of rock build up in layers
Pieces of rock are eroded and transported to the sea
Š Pearson Education 2010. Edexcel GCSE Science Activity Pack. This document may have been altered from the original.
C1.5d Rocky rocks Name
Class
Date
Igneous rocks 1
Igneous rocks form when molten rock cools down. a
What change of state happens?
b
What name is given to molten rock underground? ___________________________________
c
What name is given to molten rock above ground? ___________________________________
d
Underline the name of an igneous rock in the list below: marble
e
limestone
________________________________________________
slate
granite
chalk
Cross out the one word in each pair of words in the sentence below to make a correct sentence: Igneous rocks with (small / large) crystals form when molten rock cools (slowly / quickly).
Metamorphic rocks 2
David wrote this in his book, but he made several mistakes: ‘Metamorphic rocks form from other rocks that are heated or put under pressure at the Earth’s surface until they melt. Limestone is a metamorphic rock that forms from marble and chalk.’ Circle his mistakes, and then write down what he should have written. __________________________________________________________________ __________________________________________________________________ __________________________________________________________________
Sedimentary rocks 3
The table shows the main stages in the formation of sedimentary rocks, but they are not in the correct order. Write the numbers 1, 2, 3 and 4 in the boxes to show the correct order. Rock is broken up into pieces Over a very long time, layers are compacted together to form new rock Broken pieces of rock are eroded and transported to the sea Broken pieces of rock build up in layers
4
Underline the names of two sedimentary rocks in the list below: marble
5
slate
granite
chalk
Underline the names of three rocks that are natural sources of calcium carbonate in the list below: marble
6
limestone limestone
slate
granite
chalk
What might sedimentary rocks contain that igneous rocks would not contain? __________________________________________________________________
© Pearson Education 2010. Edexcel GCSE Science Activity Pack. This document may have been altered from the original.