AQA GCSE Chemistry Foundation (8462), Foundation tier · Atomic structure and the periodic table › Properties of transition metals
Practise Comparison with Group 1 elements. 7 exam-style questions on this subtopic, at up to four difficulty levels, with full mark schemes and a progress tracker. Free, no account needed.
How the transition metals (the central block, e.g. Cr, Mn, Fe, Co, Ni and Cu) compare with the Group 1 metals in melting point, density, strength, hardness and reactivity with oxygen, water and halogens. This is in GCSE Chemistry only, not in Combined Science. Questions often give data to compare.
Key facts
Transition metals: central block of the periodic table (examples: Cr, Mn, Fe, Co, Ni, Cu)
Compared with Group 1: much higher melting points
Compared with Group 1: much higher densities (Li, Na and K float on water)
Compared with Group 1: stronger and harder (Group 1 metals can be cut with a knife)
Compared with Group 1: much less reactive with oxygen, water and halogens
Notes
What the transition metals are
diagram
The transition metals (transition elements) are in the central block of the periodic table, between Group 2 and Group 3.
The transition metals are the central block, between Group 2 and Group 3.
The examples you need are chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni) and copper (Cu).
They are metals with similar properties to each other, which are different from the properties of the Group 1 metals.
Physical properties compared with Group 1
diagram
Melting point: transition metals have much higher melting points (iron about 1540 °C) than Group 1 metals (sodium about 98 °C).
Transition metals melt at far higher temperatures than Group 1 metals.
Density: transition metals have much higher densities (copper about 9 g/cm3). Lithium, sodium and potassium are less dense than water (1 g/cm3), so they float.
Strength and hardness: transition metals are strong and hard. Group 1 metals are soft and can be cut with a knife.
Reactivity compared with Group 1
Water: Group 1 metals react vigorously with cold water, forming hydrogen and an alkaline solution. Transition metals react very slowly or not at all: copper does not react, and iron only rusts slowly when both water and oxygen are present.
Oxygen: Group 1 metals tarnish quickly in air, so they are stored under oil. Transition metals react only slowly with oxygen at room temperature.
Halogens: Group 1 metals react vigorously. Transition metals react less vigorously and usually need heating, e.g. hot iron wool reacts with chlorine to form iron(III) chloride.
So transition metals are much less reactive than Group 1 metals. Together with their strength, this makes them useful for structures, pipes and tools.
How to answer each type of question
Compare the reactivity of a transition metal and a Group 1 metal
2 to 3 marksGrade 5
Describe what the Group 1 metal does, including the products.
Describe what the transition metal does (slowly, or no reaction).
Use a comparative word: more vigorous, less reactive.
Example. Compare the reactions of sodium and iron with cold water.
Show the model answerHide the model answer
Sodium reacts vigorously with cold water (1), producing hydrogen and sodium hydroxide, an alkaline solution (1). Iron has no visible reaction with cold water; it only rusts slowly when oxygen is also present, so it is much less reactive (1).
Predict the properties of a transition metal
2 marksGrade 5
Use the general properties of transition metals.
Make each prediction a comparison with the Group 1 metal named.
Example. Manganese is a transition metal. Predict two ways in which the properties of manganese are different from those of potassium.
Show the model answerHide the model answer
Any two: manganese has a higher melting point (1); a higher density (1); it is harder / stronger (1); it is less reactive, e.g. with water or oxygen (1).
Don’t lose marks
Saying transition metals do not react at all. Most react slowly: iron rusts, and hot iron reacts with chlorine.
Describing only one group when the question asks you to compare.
Not quoting data when the question says 'use the data'.
Mixing up density with hardness or strength.
More tips
Memory tricks
Group 1 metals are soft, light, low-melting and very reactive; transition metals are hard, dense, high-melting and much less reactive.
We build with transition metals (iron, copper); we store Group 1 metals under oil.
Think of a steel bridge compared with a knife cutting through sodium.
Exam technique
'Compare' needs a comparative word (higher, denser, less reactive) and a statement about both types of metal.
Quote numbers with their units: 1538 °C, 7.9 g/cm3.
Stick to the properties in the specification: melting point, density, strength, hardness and reactivity with oxygen, water and halogens.
What each grade needs
What you need to be able to do, from the first marks up to the top grade.
Grade 3
Locate the transition metals in the tableThey are the central block, between Group 2 and Group 3.
Grade 4
Compare melting points and densitiesTransition metals have much higher melting points and densities than Group 1 metals.
Grade 4
Compare strength and hardnessTransition metals are strong and hard; Group 1 metals are soft enough to cut with a knife.
Grade 5
Compare reactivity with oxygen, water and halogensGroup 1 metals react vigorously; transition metals react slowly, or not at all, at room temperature.
Quick recall
Cover the answers and test yourself. The app has these as flashcards that come back just before you'd forget them.
Iron reacts with chlorine only when it is heated. The product is iron(III) chloride, FeCl3. Balance the equation. ....Fe + ....Cl2 → ....FeCl3
2Fe + 3Cl2 → 2FeCl3
Sample questions
Written for this site in the style of AQA exam questions. They are not taken from real past papers.
Question 1Easy2 marks
Iron and nickel are transition metals. Sodium and potassium are Group 1 metals.
(a) Which property is typical of transition metals but not of Group 1 metals? Tick (✓) one box.[1]
High melting point
Low density
Soft enough to cut with a knife
Reacts vigorously with cold water
(b) Which metal reacts most vigorously with cold water? Tick (✓) one box.[1]
Iron
Nickel
Copper
Potassium
Show the answer and mark scheme
(a)Answer: High melting point
(b)Answer: Potassium
Question 2Medium6 marks
Iron and nickel are transition metals. Sodium and potassium are Group 1 metals.
(a) Describe how the reaction of potassium with cold water is different from the reaction of nickel with cold water.[2]
(b) Iron reacts with chlorine only when it is heated. The product is iron(III) chloride, FeCl3. Balance the equation. ....Fe + ....Cl2 → ....FeCl3[1]
(c) Sodium reacts with chlorine without being heated. What does this suggest about the reactivity of iron compared with sodium?[1]
(d) Explain why iron is used to build bridges but sodium is not.[2]
Show the answer and mark scheme
(a)Answer: Potassium reacts vigorously (fizzes, melts, burns with a lilac flame); nickel shows no visible reaction.