Nohrina swaria Periodic Table Worksheet amended PDF

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Periodic Table Assignment 1. The periodic table is arranged into groups and periods which give certain information about the elements. What information is given by the periodic table for the following from their locations in terms of groups and periods? Element

Principle Shell

Number of outer electrons

Electron configuration

Chlorine

3

7

[Ne] 3s2 3p5

Sodium

3

1

[Ne] 3s1

Boron

2

3

[He] 2s2 2p1

Carbon

2

4

[He] 2s2 2p2

Argon

3

8

[Ne] 3s2 3p6

2. What is indicated by group number? In the periodic table a group number is a column of elements who usually have the same properties because of the same number of electrons in the outermost electron shell.

3. What is indicated by period number? Each row in the periodic table is called a period which are numbered.All of the elements in the same row have the same number of orbitals.

4. Moving from left to right, the elements go from highly electropositive metals through metalloids with giant structures to the simple molecular structure of non-metals. Na Mg Al < - - - metals - - - >

Si P4 metalloid

S8 Cl2 Ar < non metals (simple molecules) >

Complete the table of physical properties below by filling in the blank boxes. Metals

Non-metals

Appearance

solids - shiny when cut

gases, liquids, dull solids

Hardness

malleable and ductile

Brittle, hard or soft.

Good conductors

poor

high

Lower

Typical properties

Electrical conductivity Melting point

5. The graph below shows the atomic radii for the elements of period 3 in the periodic table with units for radius expressed in nanometres.

0.16

0.14

0.12

0.10

0.08 Na

Mg

Al

Si

P

S

Cl

Ar

Why is the radius decreasing across the period? The radius decreasing across period 3 is because valence electrons are being added to the same energy level at the same time the nucleus is increasing in protons.The increase in nuclear charge is attracting the elctrons more strongly,pulling them closer to the nucleus.

6. Re-write the following statement filling in the blank spaces. First ionization energy is defined as “The energy required to remove one mole of electrons (to infinity) from one mole of gaseous state to form one mole of gaseous positive ions”.

7. The graph below demonstrates the first ionization energy values for period 3.

1500

1000

3s

3p

500

3s

Na

Mg

3p

Al

Si

P

S

Cl

Ar

Give a brief explanation for the drop in energy for Aluminium. The outer electron in Aluminium is in a P-shell.The 3p electron in Aluminium is slightly more distant from the nucleus then the 3s and partially screened by the 3s2 electrons aswell as the inner electrons.

8. Re-write the following statement filling in the blank spaces. Electronegativity is a measure of an atom's affinity for electrons. It increases across a period and decreases down a group. Francium is the least electronegative element and fluorine is the most electronegative element.

9. In terms of groups and periods of the periodic table, what happens to the trends in both melting and boiling point in general?

In the main group elements the melting point and the boiling point generally increase

with increasing atomic number in the family. Across the periods the trend of the melting point and the boiling point decrease from left to right, because of the valence electrons being further away from the nucleus. 10. State the mnemonic used to describe redox reactions. Use this mnemonic to state what it describes in terms of the particles to which it refers.

The mnemonic used is: Oil RiG -oxidation is loss, reduction is gain. Redox is a chemical reaction whereby electrons are gained(reduction) or lost (oxidation) to form or break bonds in chemical compounds.

11. Give the oxidation states of the following: C

-4 +3

Fe3+

+2

Fe2+ O2-

-2

He Al3+

0 +3

12. In molecules, the sum of the oxidation states adds up to _0_.

13. The oxidation state of C in CO2 = +4 and O in CO2 = -2. How is it determined which atom will have the negative value?

C02 is a neutral molecule,so the sumtotal of carbon and oxygen atoms has to be equal to 0.Carbon is +4 and Oxygen is -2,making it a -4.this balances it to 0.

14. Give the oxidation state of the element in bold from: SO2 NH3 NO2 Cl2O7 NO3¯ NO2¯ S4O62MnO42-

+4 -3 +4 +7 +3 +4 +2.5 +6

15. What will be the usual and the maximum oxidation state in compounds of: Usual Maximum

Li +1 +1

Br -1 +7

Sr +2 +2

O -2 +2

B +3 +3

N -3 +5

16. What is the oxidation state of each element in the following compounds/ions? The first row is filled in for you.

CH4 PCl3 NCl3 BrF3 PCl4+

C = -4, H = +1 P = +3, Cl = -1 N = +3, Cl = -1 Br = +3, F = -1 P =+5, Cl = -1

NH4Cl H2SO4 MgCO3 SOCl2

N = -3, H = +1, Cl = -1 H = +2,S = -6, O = -8 Mg = +2, C = +4, ) = -2 S = +4, ) = -2, Cl= -1

17. Using Roman numerals to represent oxidation state of the metal, name the following... PbO2 SnCl2 TiCl4

Lead dioxide =IV Tin (II) chloride = II Titanium Tetrachloride= IV

18. State if the following changes involve oxidation (O) or reduction (R) or neither (N) Fe2+

→

Fe3+

R

I2

→

I¯

O

F2

→

F2O

R

C2O42-

→

CO2

O

H2O2

→

O2

R

19. Balance the following half equations... Na -e Fe2+

-e

I2

+3e

→

→

Na+

→

Fe3+

1-3

I-

20.Describe and explain the trend, down the group, in the reactivity of the Group 2 elements with water. The metals in group 2 become more reactive as they go down in the group. Beryllium does not react in cold water or steam. Magnesium reacts slow in cold water and reacts faster in steam. Calcium fizzes in cold water and Strontium and Barium react in a similar way with a bit more vigorous fizz,Radium reacts more vigorously still. Each reaction gives off hydrogen gas, aswell as Magnesium, Calcium, Strontium and Barium hydroxides. 21.A student prepared an aqueous solution of calcium chloride by reacting calcium with hydrochloric acid. Ca(s) + 2HCl(aq) → CaCl2(aq) + H2(g) Using oxidation numbers, show that this is a redox reaction. The Ca CA^2 oxidation number went up form 0 to +2 and the hydrogens have gone down. H+H2 = oxidation number+1 to 0 22. Magnesium is in Group 2 of the Periodic Table. When reacted with oxygen, magnesium forms a white powder called magnesium oxide. Write the equation for the reaction of magnesium with oxygen. 2Mg + O2 = 2MgO

23. This question is about the Group 7 elements chlorine, bromine and iodine. Explain why chlorine, bromine and iodine have different physical states at room temperature and pressure. Iodine is the biggest of the 3 halogens (i.e more electrons) So the van der Waals forces between the molecules are considerably large compared to the Chlorine or

Bromine hence it’s a solid. Bromine being smaller then Iodine (i.e. less electrons) has weaker van der Waals forces between its molecules and hence it’s a liquid. Chlorine is smaller still so the van der Waals forces between its molecules are very weak indeed making it a gas at roomtemperature. 24. Radium reacts vigorously when added to water. Ra(s) _ 2H2O(l) _ Ra(OH)2(aq) _ H2(g) (i) Use the equation to predict one observation that you would see during this reaction. You will see bubbles (ii) State the name of the solution in the above reaction. Radium hydroxide

25. Explain the significance of the s, p and d blocks in the periodic table. In the periodic table the configuration can be determined of electrons of an element based on its position in the table. Hydrogen, Helium, the Alkali metals and alkaline earth metals are grouped in the Sblock.The noble gases, most of the poor metals and other non- metals are in the pblock.Then in the f-nlock(lanthanoids and actinoids,which we wont acknowledge) and everything else in the d-block. An atom of an element from the s-block will have its most outermost electrons in the ssubshell.This applies to the p-block aswell and the p subshell aswell as the d-block in the d subshell. From the information above we know Chlorine can be found in the p-block as its full electron configuration is 1s2,2s2,2p63s2,3p5.

26. The following table shows the successive ionisation energies for Carbon and Oxygen; Elemen t Carbon

1st

2nd

3rd

4th

5th

6th

7th

8th

1086.5

2352.6

4620.5

6222.7

37831

-

-

Oxygen

1313.9

3388.3

5300.5

7469.2

10989. 5

47277. 0 13326. 5

71330

84078. 0

Use this table to predict the electron configurations of these elements. Carbon There is a jump on IE from the 4th to 5th electrons and there are only 6 electrons in Carbon,so the 5th and 6th should be 1s electrons. When going from the 2nd to 3rd IE,there is a small increase in IE,this implies that there

Oxygen

is a change in subshell in the 2nd electronic energy level. The 1st and 2nd electrons that are ionised should be from 2p sub-shell and the 3rd and the 4th electrons should be from the 2s sub-shell. So the predicted electron configuration is: 1s22s22p2. The 6th electron is being removed from the 2nd quantum energy shell where as the 7th is being removed from the 1st.The first shell is much closer to the nucleus and the electrons in this shell experience no effect of shielding. This means there is a greater force of attraction between the nucleus and the 7th electron, which requires more energy to overcome. The predicted electron configuration is:1s2,2s2,2p6....