STPM Chemistry (Transition Elements)

Which of the following d-block elements is not a transition element?

• Iron

• Zinc

• Titanium

• Chromium

The first row of d-block elements has how many transition elements?

• 11

• 10

• 9

• 8

Which of the following are true about transition elements?

• Form coloured ions or compounds

• Show catalytic properties

• Appear as shiny grey solid

• Could form at least one stable simple ion with partially filled d-orbitals.

Suggest one transition element with proton number in between 20 to 26 by using chemical formula.

What is the highest oxidation state of manganese in it's compounds?

• +8

• +7

• +6

• +5

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Most of the transition elements and their compounds are heterogeneous catalysts which are useful for various reactions. The transition elements possess the catalytic power because they

• have a good adsorption characteristic

• can alter their oxidation number

• can act as reducing agents

• can form complexes

Which of the following best explains the action of a transition element as homogeneous catalyst?

• It decreases the enthalpy of reaction

• It exhibits a variable oxidation states

• It supplies energy to increase the rate of effective collision

• It supplies electrons to facilitate adsorption through the formation of temporary bonds

A solution of [Cr(H₂O)₆]³⁺ ion is violet while the solution of [Cr(OH)₄(H₂O)₂]^- ion is grey-green. This is due to the difference in

• oxidation state

• ligand

• charge

• counter ion

The chemical formula of a compound is [CoCl(NH₃)₅]SO₄. What is the IUPAC name of the compound?

• Pentaamminechlorocobalt(II) sulphate

• Chloropentaamminecobalt(II) sulphate

• Chloropentaamminecobalt(III) sulphate

• Pentaamminechlorocobalt(III) sulphate

Tris(ethylenediamine)cobalt(III) chloride is a coordination complex. Which is true about the complex?

• Its structural formula is [Co(en)₃]Cl₂

• It forms two ions in aqueous solution

• It is a square planar complex

• Its ligand is bidentate