Which of the following is most likely NOT a chemical reaction? (A)
A white powder and a clear liquid mix and the beaker holding the mixture gets cool to the touch

(B)
A white solid and a clear liquid mix and produce a bright orange, bubbling substance

(C)
A pan containing a clear liquid is place on a hot stove and begins to bubble after a few minutes.

(D)
A blue liquid and a green solid mix and produce a purple paste

B is the correct answer because bubbling is a sign of chemical reaction and production of a new substance

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.

weight of any object is given by

w = m*g

where m is mass of the object and g is the acceleration due to gravity.

for earth the value of g is 9.8 m/s^2 so

w=117.6 n m=12 g=?

117.6=12g => g=9.8 m/s^2

which is the force of gravity on earth.