Answer- A
Explanation- Because you have to look at the symbols and remember which symbol goes with each chemical, if you don't then you could get confused.
<span>So when the chemist combines Ethane (CH3CH3) and Chlorine (Cl2) with the intention of producing Chloroethane (CH3CH2Cl), the other product that's formed in this reaction is 1,2-dichloroethane (ClCH2CH2Cl) also called as Ethylene dichloride with molecular weight of 98.954 g/mol. This is a colorless oily flammable substance that weighs heaver when vaporized.</span>
Altitude. Rainfall, a hot dry day, and a hurricane are all examples of weather, not climate.
4 get of helium is 1 mole
Ppm = mass of solute mg / mass of solvent kg
0.008 * 1000 = 8.0 mg ( solute )
1000 / 1000 = 1.0 kg (solvent )
ppm = 8 / 1
= 8.0 ppm
hope this helps!