Answer:
Explanation:
In a chemical formula, the oxidation state of transition metals can be determined by establishing the relationships between the electrons gained and that which is lost by an atom.
We know that for compounds to be formed, atoms would either lose, gain or share electrons between one another.
The oxidation state is usually expressed using the oxidation number and it is a formal charge assigned to an atom which is present in a molecule or ion.
To ascertain the oxidation state, we have to comply with some rules:
- The algebraic sum of all oxidation numbers of an atom in a neutral compound is zero.
- The algebraic sum of all the oxidation numbers of all atoms in an ion containing more than one kind of atom is equal to the charge on the ion.
For example, let us find the oxidation state of Cr in Cr₂O₇²⁻
This would be: 2x + 7(-2) = -2
x = +6
We see that the oxidation number of Cr, a transition metal in the given ion is +6.
<span>The superscripts in an electron configuration represents the number of electrons and protons in an element. </span>
<span>Density is a value for
mass, such as kg, divided by a value for volume, such as m^3. Density is a
physical property of a substance that represents the mass of that substance per
unit volume. We calculate as follows:
Density = (130.278 - 20.550) / (142.419 - 130.278)/0.7918 = 7.16 g/mL</span>
Answer:
c) two different elements
Explanation:
A periodic table can be defined as the standard arrangement of chemical elements by atomic number, electronic configuration and chemical properties in a tabular form.
Generally, a proper representation of the mass number and atomic number of chemical elements is key and very important in chemistry.
Furthermore, as a rule, it should be noted that the mass number (nucleon number) is always larger than the atomic number(number of proton).
In the periodic table, all chemical elements are identified based on number of protons because it represents the atomic number.
This ultimately implies that, numbers of protons (atomic numbers) is used to differentiate an atom of one chemical element from the atom of another chemical element.
Hence, two atoms with different numbers of protons are two different elements.
For example, Hydrogen has one proton while Oxygen has 8 protons.