Periodicity

IB HL Chemistry  Topic : Periodicity 

Exercise on Periodicity (Core & AHL) Name :

1.

_____________________ :________________

Date

Phosphorus is found in period 3 and group 5 of the periodic table. (a) Distinguish between the terms period and group. [1]  _____________________________________  ________________________________________________________ _______________________________  ____________   _____________________________________  ________________________________________________________ _______________________________  ____________  (b)

State the electron arrangement of phosphorus phosphorus and explain why it is found in period 3 and group 5 of the periodic table. [3]  _____________________________________  ________________________________________________________ _______________________________  ____________  _____________________________________ ________________________________________________________ _______________________________ ____________

2.

 Table 8 of the Data Booklet gives the atomic and ionic i onic radii of elements. State and explain the difference between (a) the atomic radius of nitrogen and oxygen. [2]  _____________________________________  ________________________________________________________ _______________________________  ____________   _____________________________________  ________________________________________________________ _______________________________  ____________  (b)

the atomic radius of nitrogen and phosphorus. [1]  _____________________________________  ________________________________________________________ _______________________________  ____________   _____________________________________  ________________________________________________________ _______________________________  ____________ 

(c)

the atomic and ionic radius of nitrogen. ni trogen. [2]  _____________________________________  ________________________________________________________ _______________________________  ____________   _____________________________________  ________________________________________________________ _______________________________  ____________ 

3.

For the elements of period 3 (Na to Ar), state and explain (a) the general trend in ionization energy [2]  _____________________________________  ________________________________________________________ _______________________________  ____________   _____________________________________  ________________________________________________________ _______________________________  ____________   _____________________________________  ________________________________________________________ _______________________________  ____________ 

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IB HL Chemistry  Topic : Periodicity 

 ____________________________________________________________________  (b)

any exceptions to the general trend. [4]  ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________ 

4.

Explain the following features of the melting points of the period 3 elements. Refer to bonding and structure, and use information from Table 6 in the Data Booklet. (a)  The difference between the values for sodium and magnesium [3]  ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________  (b) The high value for silicon

[2]

 ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________  (c)

 The difference between the values for chlorine and argon [2]  ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________ 

5.

(a)

Write a chemical equation that shows which is more reactive: [2] (i) Na or K   ______________________________________________________________ 

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IB HL Chemistry  Topic : Periodicity 

(ii)

Cl2 of F2  _____________________________________________________________ 

(b)

Give a reagent which could be used to distinguish between separate solutions of potassium chloride and potassium iodide. State what would be observed when this reagent is added to each of the separate solutions of potassium chloride and potassium iodide. Write an equation for one of the reactions. [3]  ____________________________________________________________________   _   ____________________________________________________________________   _   ____________________________________________________________________   _ 

6.

Consider the 3rd period elements. (a)write the formula of their common oxides

[1]

 ___________________________________________________________________  (b)Write a chemical equation (or equations) to show if sodium oxide is acidic, basic, or amphoteric [1]  ___________________________________________________________________  (c)

Write a chemical equation (or equations) to show that sulfur dioxide is acidic, basic, or amphoteric [1]  ___________________________________________________________________ 

(d)

Write a chemical equation (or equations) to show that aluminum oxide is acidic, basic, or amphoteric [2]  ___________________________________________________________________   ___________________________________________________________________ 

7.

(a)

Describe three similarities and one difference in the reactions of  lithium and potassium with water. [4]  ___________________________________________________________________   ___________________________________________________________________   ___________________________________________________________________   ___________________________________________________________________ 

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IB HL Chemistry  Topic : Periodicity 

(b)

Give an equation for one of these reactions. Suggest a pH value for the resulting solution, and give a reason for your answer. [3]  ___________________________________________________________________ 

8.

 ___________________________________________________________________  Elements with atomic number 21 to 30 are d-block elements. (a) Identify which of these elements are not considered to be typical transition elements. [1]  ____________________________________________________________________  (b)

Complex ions consist of a central metal ion surrounded by ligands. Define the term ligand. [2]  ____________________________________________________________________   ____________________________________________________________________ 

(c)

Complete the table below to show the oxidation state of the transition element.

ion oxidation state (d)

Cr2O72-

[CuCl4] 2-

[Fe(H2O)6] 3+

Identify two transition elements used as catalysts in industrial processes, stating the process in each case. [2]  ____________________________________________________________________   ____________________________________________________________________ 

(e)

Apart from the formation of complex ions and apart from their use as catalysts, state two other properties of transition elements. [2]  ____________________________________________________________________   ____________________________________________________________________ 

9.

By reference to the structure and bonding in the compounds NaCl and SiCl4 (a) state and explain the differences in conductivity in the liquid state. [3]  ____________________________________________________________________   ____________________________________________________________________ 

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IB HL Chemistry  Topic : Periodicity 

 ____________________________________________________________________  (b)

predict an approximate pH value for a solution formed by adding each compound separately to water. [4]  ____________________________________________________________________  ____________________________________________________________________  ____________________________________________________________________ 

10.

____________________________________________________________________   Two characteristics of the d-block (transition) elements are that they exhibit variable oxidation states and form coloured compounds. (a) State two possible oxidation states for iron and explain these in terms of electron arrangements. [2]  ____________________________________________________________________   ____________________________________________________________________  ____________________________________________________________________  (b)

Explain why many compounds of d-block (transition) elements are coloured. [3]  ____________________________________________________________________   ____________________________________________________________________  ____________________________________________________________________   ____________________________________________________________________ 

(c)

Explain why compounds of s-block elements are usually white. [2]  ____________________________________________________________________   ____________________________________________________________________  ____________________________________________________________________ 

11.

(a)

Ionisation enthalpy changes for vanadium and calcium are given in the table below.

Calcium

Ionisation enthalpy changes/kJ mol–1 1st 2nd 3rd 4th 5th 590 1145 4912 6474 8144

vanadiu

650

1414

5

2828

4507

6294

6th 10 496 12

IB HL Chemistry  Topic : Periodicity 

m

362

(i) Write the chemical equation for the third ionisation of  vanadium. [2]  ______________________________________________________________  (ii)

Explain, using the ionisation enthalpy data in the table, why vanadium can form high oxidation states in its compounds whereas calcium does not form oxidation states greater than +2 in its compounds. [2]  ______________________________________________________________   ______________________________________________________________   ______________________________________________________________ 

(b)

Explain why V3+ can act as both an oxidizing agent and a reducing agent while Sc3+ is neither. [3]  ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________ 

12.

(a)

Compare the structure and bonding in AlCl3 and Al2O3. [2]  ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________ 

(b)

Describe the acid-base behaviour of AlCl 3, Na2O and P4O10. Include suitable equations in your answer. [4]  ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________ 

(c) state. [3]

Explain whether AlCl3 and Al2O3 will conduct in the solid or molten  ____________________________________________________________________   ____________________________________________________________________ 

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IB HL Chemistry  Topic : Periodicity 

 ____________________________________________________________________   ____________________________________________________________________  13.

(a)

Both zinc and nickel are d-block elements, but only nickel is a transition element. Explain the difference between these 2 terms. [2]

 ____________________________________________________________________   ____________________________________________________________________  (b)

State three factors which cause the colour change in reactions of  transition metal complexes. [3]

 ____________________________________________________________________   ____________________________________________________________________   ____________________________________________________________________ 

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