Imagine that you were in charge of creating a red and purple fireworks display. name two combinations of compounds you could use .

For red color firework we will use combination of strontium carbonate with lithium carbonate and for purple color we will use combination of strontium salts with copper salts.

Explanation:

There are various metallic salts which on performing flame test imparts characteristic color to the flame and this color is due to presence metal ions.

Color seen during the fireworks are mainly due to the presence of the metal ions present in the material from which the firework is made.

for example : strontium carbonate on flame test imparts bright red color to the flame where as barium chloride imparts green color to the flame.

The combinations of compounds are:

For red color firework we will use the combination of strontium carbonate with lithium carbonate because  combination strontium and lithium ions both imparts red color to the flame.

For purple color we will use the combination of strontium salts with copper salts because combination of strontium and copper ions imparts purple color to the flame.

your answer is c) plasma

~*"auba14"*~

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.