The oxidation number of an element is the number of electrons that are gained or lost by the element to form a chemical bond.
the net oxidation number of the ion is its charge.
compound (NH₄)₂Cr₂O₇ is made of cation - NH₄⁺ and anion - Cr₂O₇²⁻
oxidation number of ion - -2
(oxidation number of Cr x 2 Cr atoms) +(oxidation number of O x 7 O atoms )= -2
oxidation number of Cr = y
oxidation number of O = -2
(y x 2) + (-2 x 7) = -2
2y - 14 = -2
2y = 12
y = + 6
therefore oxidation number of Cr is +6
Answer:
4 atoms of oxygen.
Explanation:
The given equation is :

Here Fe and O₂ are reactants and Fe₂O₃ is a product. It is a balanced chemical reaction in which the number of atoms on LHS are equal to number of atoms on RHS.
4 atoms of iron react with 3 atoms of oxygen to form iron oxide. Hence, there are 4 atoms of reactants in this equation.
Answer:
quantum (93) the minimum quantity of energy that can be lost or gained by an atom (plural: quanta)
Explanation:
A quantum is the minimum amount of any physical entity involved in an interaction.
Answer:
NaOH
Explanation:
Sodium Hydroxide (Caustic Soda) is a base. It shares many characteristics of bleach: Albeit more powerful.
Answer:
20.3 % NaCl
Explanation:
Given data:
Mass of solute = 45.09 g
Mass of solvent = 174.9 g
Mass percent of solution = ?
Solution:
Mass of solution = 45.09 g + 174.9 g
Mass of solution = 220 g
The solute in 220 g is 45.09 g
220 g = 2.22 × 45.09
In 100 g solution amount of solute:
45.09 g/2.22 = 20.3 g
Thus m/m% = 20.3 % NaCl