Chemistry Test 203

Hint: For Na⁺, GEW=GAW

CH₃COONa undergoes anionic hydrolysis and gives basic solution (pH ≈ 9

The pH of a solution is equal to the base 10 logarithm of the H+ concentration, multiplied by -1. If you know the pH of a water solution, you can use this formula in reverse to find the antilogarithm and calculate the H+ concentration in that solution.

o-cresol (o−(CH3​)C6​H4​−(OH)) is least acidic.  −OH group and C​H3​ groups are electron releasing group. It increases the electron density on a benzene ring and does not delocalize the negative charge of phenoxide ion.

Hence, it decreases the acidity of phenol. −Cl and −NO2​ groups are electron-withdrawing groups. They delocalize the electron density of phenoxide ion. It increases the acidity of phenol.

 CH₃COOH does not ionise or dissociate completely and hence it is a weak electrolyte.

Lewis Acid is one that accepts electrons. So, usually a compound with positive charge would be acid. Also, a compound with empty orbitals. 

Lewis Base is one that donates electrons. So, usually a compound with negative charge would be considered base. Also, a compound with lone pairs. 

SiF₄​,FeCl₃​ and BF₃​ are lewis acids becuase all these compounds are having vacant orbitals to accept electon pairs

C₂​H₂​ is not a lewis acid.It's a Lewis base, as it can use a pair of electrons from the pi bond to donate to a Lewis acid.

Hence option A is correct.

A polymer sample contains chains of varying lengths and therefore molecular mass is always expressed as an average.The molecular weight of polymers are very high,due to which they are expressed in two ways:-

Number average molecular mass and weight average molecular mass.

In CsCl structure the distance the closest approach between the cation and anion is equal to half of the body of the diagonal of a cube.

Body diagonal = 3–√×3× Edge Length

=3–√×404

=699.74pm

The distance of the closest approach = 1/2× Body diagonal

=1/2×699.74 = 349.87 pm = 349.9pm

More comparable the size of anion and cation, more is the chance of Schottky defect and Na⁺ and Cl^- ions are almost comparable in size hence m ore probability to show  Schottky defect.

In pyrrole, the lone pair of electrons belonging to the nitrogen is part of the aromatic ring. However, in pyridine it is part of an sp2-hybridized orbital.