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The elements in which electrons are progressively filled in 4f-orbital are called lanthanoids.
There are 15 metallic chemical elements called lanthanoids.
Those elements are with atomic numbers from 57 to 71.
Lanthanoids belong to f-block elements because of the filling of the 4f-orbitals.
One of the lanthanoids, lutetium (chemical symbol Lu) has 14 electrons if 4f orbitals.
Electron configuration of lutetium: [Xe] 4f14 5d1 6s2
f-orbitals are similar to the d orbital, but cut in half (eight lobes instead of four).
Lanthanoids are used not as materials in catalysts, alloys, lasers and cathode-ray tubes.
More info about lanthanoids: brainly.com/question/24413965
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The digestion system does:
Ingestion, the process of eating
Mechanical digestion, the process of physically breaking food down
Etc
Basically anything that isn’t digesting/absorbing food
Answer:
8kJ/mol
Explanation:
since the forward reaction is -8kJ/mol, the backward reaction has the same enthalphy but reversed
Answer:
2.5 atm
Explanation:
V1 = 28L
T1 = 45°C = (45 + 273.15)K = 318.15K
V2 = 34L
T2 = 35°C = (35 + 273.15)K = 308.15k
P2 = 2.0atm
P1 = ?
From general gas equation,
(P1 × V1) / T1 = (P2 × V2) / T2
P2 × V2 × T1 = P1 × V1 × T2
P1 = (P2 × V2 × T1) / (V1 × T2)
P1 = (2.0 × 34 × 318.15) / (28 × 308.15)
P1 = 21634.5 / 8628.2
P1 = 2.5 atm
The initial pressure of the gas is 2.5atm