Need the answer !
which chemical reaction model is flawed?

a.

4 c2 + s8 → 4 cs2

b.

2 fe + 3 cl2 → 2 fecl3

c.

2 na + cl2 → 2 nacl

d.

p4o10 + 6 h2o → 4 h3po4

part 2

which best explains the correct answer to part 1?

a.

the products side of the equation should include water.

b.

the model shows an unbalanced number of carbon atoms.

c.

the coefficients on the reactants and products sides of the equation do not match.

d.

the same elements are on both the reactants and products sides of the equation.

Answer No 1:

The chemical model that is flawed is:

4 C2 + S8 → 4 CS2

In this reaction, there are more number of carbon atoms in the reactants but lesser number of cabon atoms in the products. For a reaction to be balanced, there should be the same number  of atoms in the reactants and products. Hence, option A does not represent a balanced equation.

Answer No 2:

The correct option is B) The model shows an unbalanced number of carbon atoms.

Consider the equation:

4 C2 + S8 → 4 CS2

In the reactants side of the equation, there are 8 atoms of carbon. In the products side there are only four carbon atoms. This shows that this equation in not balanced because of the carbon atoms.

The number of sulfur atoms remains same before the reaction and after the reaction. There are eight sulfur atoms in the reactants as well as products.

the answer is either b or c

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.