1. what is the primary standard used in this experiment? what is the molar mass of the primary standard? 2. use the chemical formula for the primary standard to write the chemical reaction for the standardization of potassium permanganate. 3. what will indicate the endpoint of the titration? 4. a 0.495 g sample of iron containing salt required 20.22 ml of 0.0194 m permanganate solution to reach the endpoint of a titration. what is the percent of iron (55.845 g/mol) in the salt?

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.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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