-level is successively filled up in:
Lanthanoids
Actinoids
Rare gases
Transition elements
Related Questions
Which lanthanoid compound is used as a most powerful liquid lasers after dissolving it in selenium oxychloride?
Cerium oxide
Neodymium oxide
Promethium sulphate
Ceric sulphate
Actinides
Have variable valency
Include element 12
Are all synthetic elements
Have only short lived isotopes
Unlike lanthanoids, actinoids exhibit a broader range of oxidation states. This difference is primarily attributed to:
The shielding effect of 4f orbitals
The comparable energies of 5f, 6d, and 7s orbitals
The greater stability of the +3 oxidation state
The larger size of actinoid atoms
Which element is NOT a lanthanide?
Cerium (Ce)
Promethium (Pm)
Actinium (Ac)
Europium (Eu)
The lanthanide contraction is responsible for the similarity in the properties of which pair of elements?
Zr and Hf
Na and K
Fe and Co
Li and Be
Actinides
Have variable valency
Include element 12
Are all synthetic elements
Have only short lived isotopes
Which statement is FALSE regarding the chemical behavior of alkali metals?
React with halogens to form covalent compounds.
Readily lose their single valence electron.
Are highly reactive.
Halides are generally soluble in water.
The primary reason for the similarity in chemical properties of lanthanides is:
The involvement of 4f orbitals in bonding.
The similar outer electronic configuration.
Their similar ionic radii.
Their radioactivity.
Which of these is an INCORRECT observation about alkali metals?
Are generally soft.
Have shiny surfaces when freshly cut.
Exhibit characteristic flame colors.
Produce a violet flame when heated.
The decrease in atomic and ionic radii of lanthanides with increasing atomic number is known as:
Actinide contraction
Lanthanide contraction
d-block contraction
Inner transition contraction
