1.2 Rocks And Building Materials

Question 1

Limestone

Answer 1

Calcium carbonate, CaCO3: very important natural chemical material.
Can be used as an abrasive for toothpastes, calcium additive in bread making and as a building material.

Question 2

Limestone reaction cycle:

Answer 2

Calcium carbonate 👉(heat) calcium oxide + carbon dioxide
CaCO3 (s) 👉 CaO (s) + CO2 (g)

Calcium oxide(quick lime) + water👉 calcium hydroxide (slaked lime)
CaO (s) + H2O (l) 👉  Ca(OH)2 (s)

Calcium hydroxide solution + carbon dioxide👉 calcium carbonate + water
Ca(OH)2 (aq) + CO2 (g) 👉 CaCO3 (s) + H2O (l)

Question 3

When carbon dioxide is bubbled through calcium hydroxide solution what happens?

Answer 3

Solution turns cloudy because a white precipitate has formed, insoluble CaCO3.

Question 4

Calcium hydroxide is an alkali so turner universal indicator…

Answer 4

Dark blue

Question 5

Why does the surface of the limestone crumble slightly when in the heat?

Answer 5

Because the limestone has decomposed and a new substance has formed.

Question 6

Thermal decomposition reaction

Answer 6

When a substance breaks down into two or more new substances when heated strongly.

Question 7

What type of reaction is it when water is added to calcium oxide?

Answer 7

Exothermic as heat is given out.

Question 8

What other test could calcium hydroxide be used for?

Answer 8

To test for carbon dioxide.

Question 9

Acid + (metal)carbonate=

Answer 9

Carbon dioxide + (metal)salt+ water

Carbonates are bases so means they neutralise acids.

Question 10

What is suck back?

Answer 10

When you remove the heat from the apparatus, the air and gas vapours inside will contract when they cool, potentially creating a vacuum.
If the bottom-end of the delivery tube was below the liquid surface then it could literally suck back some of that liquid into the apparatus.

Question 11

Metal carbonate 👉(heat)

Answer 11

Metal oxide + carbon dioxide

Question 12

When heating, if the metal in the carbonate is less reactive…

Answer 12

The carbonate decomposes more easily.

Question 13

Sulfate

Answer 13

SO4

Question 14

Nitrate

Answer 14

NO3

Question 15

What is carbon dioxide?

Answer 15

A green house gas, these gases trap heat therefore warming the earth causing global warming.

Question 16

Limestone + clay👉

Answer 16

Portland cement

Question 17

Cement + sand+(water)👉

Answer 17

Mortar

Question 18

Cement + sand + aggregate + (water) 👉

Answer 18

Concrete

Question 19

What happens when you breath in cement?

Answer 19

It will start to react with moisture in lungs.

Question 20

Cement is made in industry by…

Answer 20

Heating limestone with clay.

Question 21

What is the relationship between breaking mass and mass of aggregate in concrete?

Answer 21

As the mass of the aggregate increases the breaking point increases to a maximum point and then decreases.

Question 22

What does taking an average do?

Answer 22

Reduces the effect of random errors.

Question 23

Why might a reactive solid be cooled in a dry, argon environment?

Answer 23

Argon- noble, stable gas…not very reactive.

Dry- not react with water or carbon dioxide.

Question 24

Advantages of a building/ extending a limestone quarry?

Answer 24

Can just extend
Open up more jobs
Good place- can get to in England easily
Supports some local businesses
Will wash wheels and clean lorries
Jobs safeguarded for 20 years
More limestone production
Will be restored at end

Question 25

Disadvantages of a building/ extending a limestone quarry?

Answer 25

Destroys landscape
Destroys animals habitats
Tourism decreases, effects towns economy
Health issues e.g asthma
Business struggles
Accidents
Destroys natural beauty