Explanation:
Contributing structures are the resonating structures which are formed due to the delocalization of electrons in a molecule.
The azide ion that is 
, is a symmetrical ion, all of whose contributing structures have formal charges.
Lone pair of central nitrogen atom in azide ion is in conjugation with the neighboring nitrogen atoms.
Contributing structures of azide ion are drawn in the image attached.
Answer:
Option B. 176g/mol
Explanation:
We'll begin by writing the chemical formula for hexasodium difluoride. This is given below:
Hexasodium means 6 sodium atom
Difluoride means 2 fluorine atom.
Therefore, the formula for hexasodium difluoride is Na6F2.
The relative formula mass of a compound is obtained by simply adding the atomic masses of the elements present in the compound.
Thus, the relative formula mass of hexasodium difluoride, Na6F2 can be obtained as follow:
Molar mass of Na = 23g/mol
Molar mass of F = 19g/mol
Relative formula mass Na6F2 = (23x6) + (19x2)
= 138 + 38
= 176g/mol
Therefore, the relative formula mass of hexasodium difluoride, Na6F2 is 176g/mol
The problem above can be solved using M1V1=M2V2 where M1 is the concentration of the concentrated, V1 is the volume of the concentrated solution, M2 is the concentration of the Dilute Solution, V2 is the Volume of the dilute solution. Hence,
(3.0 M)(V2)=(250 mL)(1.2M)
V2 (3.0)= 300
V2= 100 mL
Therefore, you need 100 mL of 3.0 M HCl to form a 250 mL of 1.2 M HCl.
Answer:
flocculation is the operation in which the coagulated water must be gently mixed at a propeller speed of 15 to 20 rpm to promote the growth of the floc. ... The flocculation basin often has a number of compartments with decreasing mixing speeds as the water advances through the basin.
Explanation:
