Rock and minerals Practical 1 Periodic table PDF

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4GL501 Practical 1

4GL 501 Rocks Minerals and Gemstones Practical 1 The Periodic Table of the Elements - Some remedial chemistry The purpose of this exercise is to remind you of/ introduce you to the way we think about the chemical elements. By the end of this exercise you should be familiar with those chemical elements which are important in Geology and have some understanding of their chemical properties. This will require some knowledge of their chemical properties. Introduction Exercise 1 – element names On the copy of the periodic table provided name the 30 elements whose names have been removed from the table. Exercise 2 – characteristics of the chemical elements Complete the crossword provided (on your own)

Atomic structure and electron shells For these exercises you will need to form yourselves into groups. Each group should have in it either someone who did A-level chemistry or equivalent, or someone with a live internet connection on their phone. Exercise 3 Make a simple sketch of the structure of an atom showing the nucleus and electrons. Follow the older ‘solar-system’ or Bohr model. Exercise 4 (a) Using the data provided in the table below (overleaf – the first 20 elements), explain why electrons are distributed between the different electron ‘shells’ in the way that they are. (b) Talk about the importance of the electrons in the outermost shell. (c) What happens for elements 21- onwards. Enter the data in the table (below). (d) And 57- onwards Atomic size Exercise 5 Write down definitions/ explanations of the following terms: Atomic radius Ion Cation Anion Ionic radius Geology, University of Derby

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4GL501 Practical 1

Organisation of the Periodic Table Exercise 6. Read the section below on how the periodic table is organised and relate the different parts of the periodic table to the discussion of atomic structure that you have had above. [A historical note: the periodic table was mapped out before theory of atomic structure was well established. Our modern explanation of atomic structure validates the arrangement of the periodic Table]. Vertical patterns – ‘Groups’ Groups are families of elements which have similar chemical properties. Some groups show a trend in physical and chemical properties down the group. Groups are numbered numerically from 1A to 8A from the leftmost column (the alkali metals) to the rightmost column (the noble gases). Some of these groups have been given unsystematic names, such as the alkali metals, alkaline earth metals, halogens, and noble gases whereas others are referred to simply by their group numbers. Some of these names are given on your copy of the Table. Modern quantum mechanical theories of atomic structure explain group trends by proposing that elements within the same group generally have the same electron configurations in their outer shell which is the most important factor in accounting for their similar properties. Elements in the same group show patterns in properties such as the atomic radium. From top to bottom in a group, the atomic radii of the elements increase. Since there are more filled energy levels, valence electrons are found farther from the nucleus. From the top, each successive element has a lower ionization energy because it is easier to remove an electron since the atoms are less tightly bound.

Geology, University of Derby

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4GL501 Practical 1

Table 1. Number of electrons in each shell Element

Sym bol

Electrons in shell 1

Electrons in shell 2

Electrons in shell 3

Electrons in shell 4

1

hydrogen

H

1

-

-

-

2

helium

He

2

-

-

-

3

lithium

Li

2

1

-

-

4

beryllium

Be

2

2

-

-

5

boron

B

2

3

-

-

6

carbon

C

2

4

-

-

7

nitrogen

N

2

5

-

-

8

oxygen

O

2

6

-

-

9

fluorine

F

2

7

-

-

10

neon

Ne

2

8

-

-

11

sodium

Na

2

8

1

-

12

magnesiu m

Mg

2

8

2

-

13

aluminiu m

Al

2

8

3

-

14

silicon

Si

2

8

4

-

15

phosphor us

P

2

8

5

-

16

sulfur

S

2

8

6

-

17

chlorine

Cl

2

8

7

-

18

argon

Ar

2

8

8

-

19

potassiu m

K

2

8

8

1

20

calcium

Ca

2

8

8

2

21 22 23 24

Horizontal patterns – ‘Periods’ Although groups generally have more significant periodic trends, there are regions where horizontal trends are more significant than vertical group trends, such as the lanthanides and actinides. Elements in the same period show trends in atomic radius, ionization energy, and electronegativity. Moving left to right across a period, atomic radius usually decreases. This occurs because each successive element has an added proton and electron which causes the electron to be drawn closer to the nucleus. This decrease in atomic radius also causes the ionization energy to increase when moving from left to right across a period. The more tightly bound an element is, the more energy is required to remove an electron. Electronegativity increases in the same manner as ionization energy because of the pull exerted on the electrons by the nucleus. Electron affinity also shows a slight trend across a

Geology, University of Derby

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4GL501 Practical 1

period. Metals (left side of a period) generally have a lower electron affinity than nonmetals (right side of a period) with the exception of the noble gases. Series Groups of like elements are often color-coded and named in a periodic table of elements. This kind of group is often referred to as a series. Groups can include both rows and periods. The transition metals are one such series. Blocks Because of the importance of the outermost electron shell, the different regions of the periodic table are sometimes referred to as blocks, named according to the subshell in which the "last" electron resides. The s-block comprises the first two groups (alkali metals and alkaline earth metals) as well as hydrogen and helium. The p-block comprises the last six groups which are groups 3A to 8A and contains, among others, all of the metalloids. The d-block comprises groups 3B to 2B and contains all of the transition metals. The f-block, usually offset below the rest of the periodic table, comprises the lanthanides and actinides. Exercise 6. Write down definitions/ explanations of the following terms: Atomic nucleus Atomic number Atomic mass Atomic weight Isotope Show the standard notation for an isotope of U (uranium)

Geology, University of Derby

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4GL501 Practical 1

1

2

3 4 5

7

6

8

9

10

13

14

15

16

17

18

19

Geology, University of Derby

11

12

Across 1 The lightest inert gas. (6) 4 The element we need to breathe. (6) 5 Alkaline metal in table salt. (6) 7 Inert gas used to make bright city lights. (4) 8 2nd place in the Olympics. (6) 10 An important element in bones. (7) 13 A radioactive element often used in nuclear power stations. (7) 14 Poison gas in WWI. (8) 15 A famous poison that turns your tongue black. (7) 17 A metal sought after during the Klondike. (4) 18 The element diamonds are made from. (6) 19 This metal is used along with carbon to make steel. (4) Down 2 Heavy metal used in paints, batteries, and radiation shields. (4) 3 The most common element in the universe. (8) 6 A liquid metal that was used in thermometers. (7) 7 Most common element in the earth's atmosphere. (8) 9 A component of gunpowder that smells like rotten eggs. (7) 11 A metal used in foil. (World Spelling) (9) 12 A metal used in wires. (6) 15 The most common inert gas in the atmosphere. (5) 16 Element used to make semiconductors (computer chips). (7)

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4GL501 Practical 1

Geology, University of Derby

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