The number average weight of a poly(styrene-butadiene) alternating copolymer is 1,350,000 gmol"! . determine the average number of styrene and butadiene mer units per molecule.

8544

Explanation:

Given:

An alternating copolymer,

thus, the number of both types of repeat units will be the same.

average weight of a poly(styrene-butadiene)  = 1,350,000 g/mol

and,

there are 8 atomes of carbon and 8 atoms of hydrogen  in the styrene repeat unit,

also, There are 4 atoms of carbon and six atoms of hydrogen in butadiene repeat units.

Therefore,

when the styrene-butadiene is combined the total number of carbon atoms in a molecule will be ( 8 + 4 ) i.e 12 atoms

and, the total  number of Hydrogen atoms will be ( 8 + 6 ) i.e 14 atoms

Therefore, the total molecular weight will be

m = 12 × Molecular weight of the carbon + 14 × Molecular weight of the hydrogen

or

m = 12 × 12 g/mol + 14 × 1 g/mol

or

m = 158 g/mol

Now,

the average number of styrene and butadiene mer units per molecule will be

=  

= 8544.30 ≈ 8544

d: the voltage of the secondary coil is less than that of the primary coil.

im not suree sorry if wrong

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."