National 4/5 Unit 1 Atomic Structure & Bonding Problem Sheets

Prestwick Academy Chemistry department

National 4/5 Unit 1– Atomic structure & Bonding Problem sheets

Unit 1.2 Revision

1.

a. Which of the above graphs could represent an endothermic reaction?

b. Give an everyday example of an exothermic reaction.

c. State the effect on the temperature on the surroundings when:

(i) an endothermic reaction takes place?

(ii) an exothermic reaction takes place?

2. The following questions refer to the rate graph shown below.

a. Identify which graph represents the reaction with the fastest rate?

b. The rate graphs correspond to 2 reactions. Which graph is likely to represent the reaction carried out at the highest temperature?

c. At which stage in the reaction is the rate quickest?

d. Why does the slope level off gradually over time?

Atomic structure

3.

a. What name is given to the tiny particle that all substances are made from?

b. i) What name is given to the core at the centre of these particles?

ii) What is the charge of the core?

iii) What name is given to the particles that move around the core?

c. Explain why atoms are neutral.

4. Copy and complete the following table.

Particle

Mass

Charge

Location in atom

5. Copy the diagram of the atom into your jotter and label the following parts:

nucleusenergy levelelectron

neutronproton

Atomic number/mass number

6. Explain what is meant by:

a. Atomic number

b. Mass number

7. Atoms are made up of protons, neutrons and electrons.

A

B

C

D

E

a. Identify the two numbers that are the same in a neutral atom

b. Identify the mass number of an atom

c. Identify the two numbers that identify the atomic number of an atom

8. Complete the following table.

9.

a. Use your Data booklet to complete the following table.

Element

Atomic number

[Question 9 continued…]

b. What value would you predict for the melting point of francium (Fr)?

c. Describe the trend between atomic number and the melting point for the Group 1 metals using the above table?

Electron arrangement/electroncloud diagrams

10.

a. Name the elements with the following electron arrangements

(i) 2,8,1(ii) 2,8,8(iii) 2,4(iv) 2,7(v) 2,8,4

b. Which two of the above elements will have similar chemical properties?

11. Draw electron cloud diagrams for the following elements.

a. Calcium b. Lithium c. Silicon d. Hydrogen e. Chlorine

Nuclide notation

12. Give the number of protons, neutrons and electrons present in the following atoms:

193916

a. F b. K c. O

919 8

14

13. An atom of carbon can be represented by the symbol C

6

Identify the correct two statements about this carbon atom.

14. 23

An atom of sodium can be shown as Na.

11

Write each atom below in a similar way. (Use the Data booklet for some information)

a. An oxygen atom with 10 neutrons.

b. An atom with atomic number 6 with 7 neutrons.

Isotopes/relative atomic mass

15,

a. Which of the following atoms are isotopes?

17 18 18 15 17

A B C D E

8 9 10 8 7

b. Explain your answer.

16.

20 22

Ne and Ne are two different kinds of neon atom.

10 10

a. In what way are the two kinds of neon atom different?

b. Explain why they can be regarded as atoms of the same element.

c. What name is given to these kind of atoms?

d. The relative atomic mass of neon is 20.2. How is this possible when the mass number is a whole number?

17.

a. The elements calcium and strontium have similar chemical properties.Suggest why calcium and strontium have similar chemical properties.

b. Explain why strontium has a relative atomic mass of 87.6 yet no strontiumatom has this mass.

18. 39

The most common isotope of potassium is K.

19

a. How many protons, neutrons and electrons are in an atom of carbon?

b. How do isotopes of potassium differ from each other?

Past paper questions

26.

27.

28. Copper is made up of two different types of atom.

(a) Complete the table to show the numbers of protons and neutrons in each type ofcopper atom.

(b) What term is used to describe the different types of copper atom?

29. The diagram represents the structure of an atom.

(a) Complete the tables.

[Question continues over]

(b) Ernest Rutherford used alpha particles to confirm the structure of the atom. The table shows the number of protons, electrons and neutrons in an alpha particle.

(i) What is the atomic number of an alpha particle?

(ii) When alpha particles are passed through an electric field, which letter in the diagram shows the path taken by them?

30. Atoms contain particles called protons, neutrons and electrons. The nuclide notation of the sodium atom is shown.

(a) Complete the table to show the number of each type of particle in this sodium atom.

(b) Electrons are arranged in energy levels.

(i) Draw an electron cloud diagram to show how the electrons are arranged in a sodium atom.

(You may wish to use page 1 of the data booklet to help you.)

(ii) Explain what holds the negatively charged electrons in place around the nucleus.

Groups of atoms (National 4)

31. What is meant by a molecule?

32. State which compounds below have covalent bonds between their atoms.

sodium chloridehydrogen fluoridelithium oxide

nitrogen dioxideiron oxidebrass (zinc + copper)

sulphur chloridecalcium carbonatecarbon monoxide

33. State which of the substances below have metallic bonds.

Hydrogenoxide, magnesium, carbonmonoxide, hydrogen, brass, iron

34. State the type of bonding present in each of the following substances.

Sulphur dioxide, lead nitrate, iron, carbon chloride, zinc, iron oxide

Covalent bonding (National 4)

35. Explain how a covalent bond holds two hydrogen atoms together in H2?

36. The diagram opposite shows a hydrogen molecule. H---H

1. Name the type of bond that holds the hydrogen atoms together.
2. What name is given to the particle formed when non-metal atoms combine (i.e. H2)?
3. Why is hydrogen (H2) described as diatomic and water (H2O) triatomic?

Electron cloud diagrams (National 5)

37. (i) Firstly, write the electron arrangement of the following atoms and then draw their electron cloud diagram.

1. carbon (6C)
2. chlorine (17Cl)
3. hydrogen (1H)

(ii) The formation of hydrogen carbide using electron cloud diagrams is shown below.

(X4) + 

(iii) Use similar diagrams to show the formation of hydrogen chloride, nitrogen hydride and carbon chloride

Shapes of molecules (National 5)

38. Draw diagrams to show the shape of each of the following molecules.

a. carbon hydride - CH4b. nitrogen chloride - NCl3

c. hydrogen bromide - HBrd. hydrogen sulphide - H2S

Properties of substances (National 4/5)

39. Which box (or boxes) in the grid below shows?

1. a non-metallic conductor (N4)
2. a substance that conducts when molten (N4)

c. a substance that does not conduct when either solid or molten (N4)

d. a substance that conducts when solid (N4)

e. a covalent substance (N4)

1. a substance that forms an electrolyte in solution (N5)

(National 5)

40. During electrolysis of a molten compound, the elements lead and bromine were formed.

1. At which electrodes (i.e. positive or negative) does each element form?
2. Name the compound being electrolysed.
3. What type of bonding is present in the compound?
4. Will the compound conduct electricity in the solid state?

41. Name the particles that carry the current in each of the following substances.

a. molten sodium chlorideb. solid iron

c. potassium chloride solutiond. liquid mercury.

42. Copper chloride solution was electrolysed.

1. What is meant by copper chloride was electrolysed?

1. Name the gas formed at the positive electrode and use page 7 of your Data booklet to write the ion-electron equation for the reaction.
2. Name the solid formed at the negative electrode and write the ion –electron equation for the reaction.
3. Explain why solid copper chloride does not conduct electricity.

43. Explain fully whycovalent compounds do not conduct electricity?

1. metals conduct in the solid state?
2. solid ionic compounds do not conduct electricity?
3. why ionic compounds have a high melting point?
4. carbon has a high melting point but most covalent compounds have a low melting point?

44. John was investigating the properties of five different elements.

His results are shown in the grid.

1. Identify the element that could be carbon.
2. John thinks that only solid metallic elements conduct electricity.

Identify the two elements that do not support this view.

Past Exam Paper Questions

45. Study the table and use the information

to work out the expected colour of

1. nickel chloride
2. potassium dichromate
3. ammonium nitrate
4. ammonium nickel sulphate

46.a. Name the two types of covalent structure.

b. On page 6 of the Data booklet look at the table with the heading ‘Covalent’

State the melting points of carbon dioxide and silicon dioxide.

1. Name the type of structure present in each and use this to explain the large difference in melting points.

51. The properties of substances are related to bonding.

a. Identify the substance which is an ionic compound.

b. Identify the substance which is a covalent network compound.

52. Ions are formed when atoms lose or gain electrons.

Which two elements form ions with the same electron arrangement as argonatoms?

53.a. Why does copper metal conduct electricity?

b. Copper reacts with chlorine to form copper chloride.

(i)Name the type of bonding present in copper chloride.

(ii)The chloride ions in copper chloride have a stable electron arrangement.

How do they achieve this arrangement?

1. Copper chloride solution can be electrolysed to produce copper and

chlorine.Complete the diagram below to show this electrolysis. [Show clearly where copper and chlorine are formed]

54. The atoms in a chlorine molecule are held together by a covalent bond.A covalent bond is a shared pair of electrons.Explain how this holds the atoms together.

55.

1. Identify the two particles with the same number of neutrons.
2. Identify the two atoms that are isotopes.
3. Identify the two particles that have the same electron arrangement as neon.

Unit 1 Homework ink exercise (1)

*STUDY TIP - All questions should be completed in your homework jotters in time for the deadline. You should use your summary sheets to help you answer the questions.*

1. Copy and complete.

‘The centre of the atom is called the ______. It has a ______charge.

Moving around the centre of the atom are tiny particles called ______.

These particles have ______charge’ (2)

2. Copy and complete the following table.

(6)

3. Naturally occurring silver (atomic number 47, relative atomic mass 108) consists

of a mixture of two isotopes with mass number 107(107Ag) and 109(109Ag).

(a) Identify the two true statements.

A

B

C

D

E

(b) Explain why the relative atomic mass of an atom is often not a whole number (e.g. Cl has a relative atomic mass of 35.5 a.m.u)?

(c) The relative atomic mass of a silver atom is 108. What does this suggest about the abundance of the silver isotopes 107Ag and 109Ag? (4)

4. Calculate the number of protons, electrons and neutrons for the following IONS?

(a) 24 2+ (b) 14 3- (c) 18 -

Mg N F

12 7 9 (3)

Unit 1 Homework ink exercise (2)

1.

iron, sodium chloride solution, water (H2O), sulphur, solid iron oxide

(a) From the list of substances above name two covalent substances

(b) From the list of substances above name an ionic substance that can conduct electricity

(c) Carbon exists in 2 forms, graphite and diamond.

(i) Which of the 2 forms is capable of conducting electricity.

(ii) What name is given to the particle responsible for this physical property.

(4)

2.

(a) Name the type of bond that holds non-metal atoms together.

(b) Draw electron cloud diagrams to show how a bond is formed between hydrogen and fluorine atoms in a molecule of hydrogen fluoride.

(c) In a molecule of hydrogen fluoride atoms share electrons.Explain how the shared electrons can hold the atoms together.

(d) Draw the true shape of the molecules CCl4 and NF3. (5)

3. The table below shows some properties of substances W, X, Y and Z: ×= conducts o = does not conduct

W

X

Y

Z

From the information given in the table state whether substances W, X, Y and Z are

Simple covalent, Network covalent, Ionic, Metallic (3)

4. When the electrolyte sodium chloride is electrolysed sodium is produced at the negative electrode and chlorine at the positive electrode.

(a) Draw a diagram of the apparatus that could be used to electrolyse the sodium chloride?

(b) Explain the meaning of the term ‘electrolyte’.

(c) Write the ion-electron equation for the formation of chlorine. (4)

5. The following pictures represent the structures of covalent networks, covalent molecules and ionic lattices.

A BC

Match the type of structure to the correct diagram. (2)

1