A-level Chemistry: The Transition Metals Intro.

What Are The d-block Elements?

What Are The d-block Elements?

The elements that sit at the middle of the periodic table.

What Is A Transition Metal?

A metal/d-block element that can from at least one stable ion with an incomplete d-subshell.

How Many Electrons Can The D-Subshell Hold?

Up to 10 electrons.

Why Aren’t Zinc And Scandium Transition Metals?

Because they don’t form stable ions with an incomplete d-subshell.

Why Do Electrons Fill Up Singly First Before Pairing Up When Considering Electron Configuration?

Because electrons repel each other.

What Is The Electron Configuration Of Titanium (Ti)?

1s2, 2s2, 2p6, 3s2, 3p6, 3d2, 4s2.

OR

[Ar], 3d2, 4s2.

What Is The Electron Configuration Of Chromium (Cr)?

1s2, 2s2, 2p6, 3s2, 3p6, 3d5, 4s1.

OR

[Ar], 3d5, 4s1.

What Is The Electron Configuration For Copper (Cu)?

1s2, 2s2, 2p6, 3s2, 3p6, 3d10, 4s1.

OR

[Ar], 3d10, 4s1.

Copper’s Short-Hand Electron Configuration Is [Ar] 3d10, 4s1. Why Is It Not [Ar] 3d9, 4s2?

Because one of the electrons from the 4s orbital moves into the 3d orbital in order to create a full, more stable, 3d sub-shell.

Chromium’s (Short-Hand) Electron Configuration Is [Ar] 3d5, 4s1. Why Is It Not [Ar], 3d4, 4s2?

Because one of the electrons from the 4s orbital moves into the 3d orbital in order to create a half-full, more stable, 3d sub-shell.

Scandium Forms A Stable Ion Of Sc³⁺. Why Is Scandium Not Considered A Transition Metal?

Transition metals are metals that form stable ions with incomplete 3d-subshells.

Though Sc has an incomplete d-subshell, its stable ion Sc³⁺

has an empty d-subshell.

Scandium is therefore not a transition metal.

Zinc Forms A Stable Ion Of Zn²⁺. Why Is Zinc Not Considered A Transition Metal?

Transition metals are metals that form stable ions with incomplete 3d-subshells.

Both Zn and its stable ion Zn²⁺ have a full d-subshell.

Zinc is therefore not a transition metal.

What Are The General Properties Of Transition Metals?

1. They have variable oxidation states

2. Form coloured ions in solution

3. Are good catalysts

4. They can form complex ions

What Ions Does Vanadium (V) Form?

V²⁺

V³⁺

VO²⁺

VO2⁺

What Ion(s) Does Manganate (Mn) Form?

Mn²⁺

MnO4⁻

What Ion(s) Does Iron (Fe) Form?

Fe²⁺

Fe³⁺

What Ion(s) Does Cobalt Form?

Co²⁺

What Ion(s) Does Nickel (Ni) Form?

Ni²⁺

What Ion(s) Does Copper (Cu) Form?

Cu²⁺

What Ion(s) Does Chromium (Cr) Form?

Cr³⁺

Cr2O7²⁻

What Colours Are Vanadium (V)’s Ions When Reacting In Aqueous Solution?

V²⁺: Violet

V³⁺: Green

VO²⁺: Blue

VO2⁺: Yellow

What Colours Are Chromium (Cr)’s Ion(s) In Aqueous Solution?

Cr³⁺: Violet

Cr2O7²⁻: Orange

What Colours Are Manganese (Mn)’s Ion(s) In Aqueous Solution?

Mn²⁺: Very pale pink/Colourless

MnO4²⁻: Green

MnO4⁻: Purple

What Colour Are Iron (Fe)’s Ion(s) In Aqueous Solution?

Fe²⁺: Pale green

Fe³⁺: Yellow

What Colours Are Cobalt (Co)’s Ion(s) In Aqueous Solution?

Co²⁺: Pink

What Colour Are Nickel (Ni)’s Ion(s) In Aqueous Solution?

Ni²⁺: Green

What Colour Are Copper (Cu)’s Ion(s) In Aqueous Solution?

Cu²⁺: (Pale) blue