Answer:Option (3) less than the sum of its components' masses
Explanation:
Answer : The chemical formula for the compound is, 
Explanation :
When the element 'M' react with the
to give
.
The balanced chemical reaction is,

In this reaction, 'M' is in mono-atomic form and
is in diatomic form.
By the stoichiometry,
2 moles 'M' react with the 1 mole of
to give 2 moles of
.
Therefore, the chemical formula of the compound is, 
The answer is transition metals because they have no specific charge except for 1 or 2 of them
Answer:
hypochlorite ion
Explanation:
The hypochlorous acid, HClO, is a weak acid with Ka = 1.36x10⁻³, when this acid is in solution with its conjugate base, ClO⁻ (From sodium hypochlorite, NaClO) a buffer is produced. When a strong acid as HCl is added, the reaction that occurs is:
HCl + ClO⁻ → HClO + Cl⁻.
Where more hypochlorous acid is produced.
That means, the HCl reacts with the hypochlorite ion present in solution
Adding (S2O3)2- would affect the reaction mechanism that involves this ion. From the reaction mechanism given above, the equilibrium of step 2 would be affected. Adding the stock solution of (S2O3)2- would shift the equilibrium to the right thus making more products of the said mechanism. Also, the reaction rate of this step would occur faster than the original rate. This is based on Le Chatelier's Prinicple which states that a corresponding change would happen to the equilibrium of a reaction when pressure, concentration of the substances or temperature is changed. So, that after the addition, a color change would appear immediately because I3- would be removed slowly from solution, and would therefore be able to react with starch.