Answer:
The number of protons in an atom is different than the atom’s total mass.
Explanation:
Mendeleev knew only that, with some anomalies, the properties of elements varied periodically with their atomic masses.
Moseley's X-ray experiments enabled him to remove these anomalies and to show that the properties of elements varied with their atomic numbers.
Chadwick later discovered that the mass differences were caused by the presence of neutrons.
It's b. calcium
because the outer electron structure in all of that element is similar, they have the same chemical and physical properties.<span />
Explanation:
for having a ionic bond we need great delta X that we see in electropositive atom (Na) and an electronegative atom(F)
Analyze the Name of complex Compound.
T<span>etracarbonylplatinum(iv) chloride
So, there are,
4 Carbonyl groups = 4 CO = (CO)</span>₄
1 Platinum Metal = 1 Pt = Pt
Unknown Chloride atoms = ?
In complexes positive part is always named first, so the sphere containing Pt and carbonyl ligands is written first,
[Pt (CO)₄]
The charge on sphere is +4 because CO ligand is neutral, and Pt has a Oxidation state of four as written in name (IV),
So,
[Pt (CO)₄]⁴⁺
Now, in order to neutralize +4 charge we should add 4 Chloride ions, So,
[Pt (CO)₄] Cl₄
