A) solid
b)liquid
c)liquid
d)gas
<u><em>Answer:</em></u>
- The correct structure of phosphoric acid is A.
<u><em>Explanation</em></u>
- P should form five covalent bonds. In this strcuture P form three single bond with 3-hydroxyl groups while one single bondformed with oxygen. As oxygen will form two bonds , it carry negative charge, while P should form five bond but here it is forming 4 bonds due to this P has positive charge but overall structure contain neutral charge due to cancellation of positive and negative charges. Beside this, there are 3 H, Four O and One P according to formula H3PO4.
A chemical change creates a new substance
Answer:
106,504 g/mol
Explanation:
The two repeat units at the polymer are the acrylonitrile and the butadiene. If the fraction of repeat of butadiene is 0.27, the fraction of repeat of units of acrylonitrile must be 0.73.
The acrylonitrile repeat unit has 3 carbons atoms, 1 nitrogen atom, and 3 hydrogen atoms. So, the molecular weigth for it is:
mac = 3*mC + 1*mN + 3*mH
mC = 12 g/mol; mN = 14 g/mol; mH = 1g/mol
mac = 3*12 + 14 + 3*1 = 53 g/mol
The butadiene repeat unit has 4 carbons atoms and 6 hydrogen atoms. Thus, the molecular weight is:
mbu = 4*12 + 6*1 = 54 g/mol
The average repeat unit molecular weight is the fractions multiplied by the molecular weight of the repeat unities:
m = 0.73*53 + 0.27*54 = 53.27 g/mol
The number-average molecular weight is the average repeat unit molecular weight multiplied by the degree of polymerization:
M = 53.27*2000
M = 106,504 g/mol
