Question

using the periodic table, what is the predicted last orbital notation for lanthanum (la)?
6s²
5f¹
5d¹
4f¹
what is the definition of temperature?
the amount of space a substance occupies.
the average kinetic energy of particles.
the relative size of particles.
force applied per unit area.
all orbitals hold up to 2 electrons.
true
false

Explanation:

Question 17

Lanthanum (La) is in period 6 and group 3. The electron - filling order for elements in the lanthanide series (La is the first element of the lanthanide - like behavior, although it is in the d - block in some periodic table representations). The electron configuration of La is [Xe]6s²5d¹. So the last orbital notation is \(5d^{1}\).

• The amount of space a substance occupies is the definition of volume.
• Temperature is defined as the average kinetic energy of particles. As the temperature of a substance increases, the average speed (and thus kinetic energy) of its particles increases.
• The relative size of particles is not the definition of temperature.
• Force applied per unit area is the definition of pressure.

According to the Pauli exclusion principle, each orbital can hold a maximum of 2 electrons with opposite spins. This is a fundamental rule in electron - filling of orbitals.

Answer:

C. \(5d^{1}\)

Question 18