Answer:
NaNO₃
Explanation:
A precipitate is a compound or a salt formed from a precipitation reaction and does not dissolve in water and therefore will exist in solid state.
From the choices given precipitation reaction will occur between;
- Fe(NO₃)₃(aq) + 3NaOH(aq) → Fe(OH)₃(s) + 3NaNO₃(aq)
- Cu(NO₃)₂(aq) + 2NaOH(aq) → Cu(OH)₂(s) + 2NaNO₃(aq)
- FeSO₄(aq) + 2NaOH(aq) → Fe(OH)₂(s) + Na₂SO₄(aq)
Fe(OH)₃, Cu(OH)₂, and Fe(OH)₂ are precipitates.
From the rules of solubility, hydroxides are insoluble except Ca(OH)₂ which is slightly soluble and hydroxides of ammonium and alkali metals.
Answer:
A
Explanation:
Iron has the ground state electronic configuration [Ar]3d64s2
Fe2+ has the electronic configuration [Ar]3d6.
In an octahedral crystal field, there are two sets of degenerate orbitals; the lower lying three t2g orbitals, and the higher level two degenerate eg orbitals. Strong field ligands cause high octahedral crystal field splitting, there by separating the two sets of degenerate orbitals by a tremendous amount of energy. This energy is much greater than the pairing energy required to pair the six electrons in three degenerate orbitals. Since CN- is a strong field ligand, it leads to pairing of six electrons in three degenerate orbitals
Answer:
265.2amu
Explanation:
Given parameters:
Atomic mass = 254.9amu
Abundance of isotope 1 = 72%
Atomic mass of isotope 1 = 250.9amu
Abundance of isotope 2 = 100 - 72 = 28%
Unknown:
Atomic mass of isotope 2 = ?
Solution:
To find the atomic mass of isotope 2, use the expression below:
Atomic mass = (abundance of isotope 1 x atomic mass of isotope 1) + (abundance of isotope 2 x atomic mass of isotope 2)
Now insert the parameters and find the unknown;
254.9 = (0.72 x 250.9) + (0.28 x Atomic mass of isotope 2)
254.9 = 180.648 + 0.28x atomic mass of isotope 2
254.9 - 180.648 = 0.28x atomic mass of isotope 2
74.25 = 0.28 x atomic mass of isotope 2
Atomic mass of isotope 2 = 265.2amu
