Well the the answer is 70.8c but if you round it up it is 71c which I choice and got it correct so the answer is 71c
C. C and Pb; Carbon and Lead being in the same group.
Answer: a)
: negative
b)
: positive
c)
: positive.
d)
: negative
e)
: positive.
f)
: positive.
Explanation:
Entropy is the measure of randomness or disorder of a system. If a system moves from an ordered arrangement to a disordered arrangement, the entropy is said to decrease and vice versa.
is positive when randomness increases and
is negative when randomness decreases.
a) 
As ions are moving to solid form , randomness decreases and thus sign of
is negative.
b) 
As solid is changing to gas, randomness increases and thus sign of
is positive.
c) 
As 2 moles of reactants are converted to 4 moles of products , randomness increases and thus sign of
is positive.
d) 
As gas is changing to solid, randomness decreases and thus sign of
is negative.
e) 
As 7 moles of reactants are converted to 8 moles of products , randomness increases and thus sign of
is positive.
f)
As solid is changing to gas, randomness increases and thus sign of
is positive.
Answer: 1. Ethylene is a stable molecule with two carbon atoms connected by a double bond. Polyethylene is made by the reaction of multiple ethylene molecules in the presence of a catalyst.
2. The term “plastics” includes materials composed of various elements such as carbon, hydrogen, oxygen, nitrogen, chlorine, and sulfur.
3. Polyethylene (PE) is made by the reaction of multiple ethylene molecules in the presence of catalysts to break the double bond and connect the carbon atoms into a chain . The longer the chain, the higher the molecular weight. Polymers can have molecular weights in the millions.
Explanation: