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Flashcards in C5 Deck (19):
1

What are the earth's spheres?

2

what is the lithosphere made up of?

-rocks

-slicates

-silicon combined with oxygen

-contains hydrocarbons as oil

carbon hidden in calcium carbonate of chalk and limestone

3

What is the difference in strength between intermolecular forces and atomic bonds?

oxygen and hydrogen molecules have weak attractive forces between molecules of the same type.

-atomic bonds are really strong and require large forces and temperature to break bonds.

4

What are the properties of water?

less dense than gases like oxygen

-greater tendenacy to stick together because of look at photo

a water molecule is slightly positive on one side and slightly negative on the other side, which allows them to be more compact than other gases

-more dense than ice as can be compacted

-salts dissolve in water

5

Why is seawater salty?

-salt can dissolve in water

-rocks eroded in water

-water salty

6

What is a covalent bond and which types of elements do they connect?

-non-metal and metal elements

-e.g. Na and Cl

-covalent bond is where the atoms share a pair or pairs of electrons

-atoms were held together because the positively charged nuclei of both atoms are attracted to the negatively charged shared pair of electrons

7

What id the strength of atomic and molecular forces in covantly bonded atoms?

-weak forces between molecules oxygen

-strong covalent atomic bonds

-results in low melting and boiling points, but it is very difficult to break the atomic covalent bonds

8

What is an ionic bond?

-the attraction between a positvely charged atomand anegatively charged atom

high melting and boiling points

So4(-2)-ionic but called a molecular ion

9

How can we test if positive ions are present in a compound and what are they?

-add adilute acid e.g. sodium hydroxide to compounds

-Positive if a precipitateof an insolublecompound forms during the reaction

-colour of the precipitate may help identify it

calcium Ca(2+)-white precipitate

copper Cu(2+)-Light blue precipitate

iron(11) Fe(2+)-Green precipitate

iron(111) Fe(3+)-Red-brown precipitate

Zinc Zn(2+)-white precipitate(excessis soluble)

 

10

How do you test if negative ions are present in a compound?

-By addind negative Group 7 elements to a dilute silver nitrate or barium chloride

Br-cream precipitate

I-yellow precipitate

Cl-white preciitate

acidify with dilute nitric acid, then addsilver nitrate

11

What are some examples of metal, mineralsand ores and where are they found?

-found in the lithosphere

-minerals are solids with atoms or ions arranged in a regualar lattice

e.g.carbon in the form of graphite and diamond

-silcon+oxygen join together as the mineral quartz

-many metals are oxides

e.g.Copper, zinc

-extracted by combining with carbon

-reduction reaction e.g. less oxygen

2Zinc+carbon=2Zinc+co2

12

What are the differences and smilarities between diamond and graphite?

Diamond-giant covalent structure

-made up of carbon that is covalently bonded

-strong structure

-high melting and boiling point

-insoluble

-no free electrons

-does not conduct electricity therefore

Graphite- giant covalent structure

-made up of covalently bonded carbon atoms

- in graphite, each carbon is bonded to 3 or less crbon atoms in sheets

sheets are strong

weak intermolecular forces between the sheets

-free electrons allow the material to conduct electricity

13

What are some of the issues of extracting metal?

-how can the ore be reduced?

-the more reactive a metal is, the harder it is to reduce the ore

Is there a good supply of ore?-

-it may not be worth extracting

-cost

what are the energy costs?

-it may take a lot of energy to extract the metal

What is the impact on the environment?

-could release a harmful toxin

 

14

What is a metallic bond?

-positive protons swiming in a sea of negative electrons in a lattice

-electrons can move freely

-can conduct electricity

strong bonds

-high melting points

15

What are some properties and uses of metals?

-strong+malleable

-lead,mecury are poisinous

-waste can destroy habitats and soils

-lead used to make betteries for vehicles

-copper used for wire

-modern batteries use lithium, not toxic difficult to extract

16

How do you calculate the relative atomic mass of atoms?

E.g. water=H2O

(2times1) +16=18

17

How do you calculator the percentage of metal in a mineral?

=total mass of metal of atoms divided by gram formula mass

gram formula mass=relative formula mass in grams

18

 How electrolysis is used to extract aluminium from its ore?

compound=aluminium ore=electrolyte

-used to extract only more reactive metals as others can be reduced using carbon

-negative electrode attracts positive Al(3+)

-Positive electrode attracts negative O(2-) 

Al(3+)+3e-=Al

2O(2-)=O(2)+4e-

19

How is a metal made and recycled?