Question

mL Starting volume 3-bromo-3-ethyl pentane_ 4.77 Starting volume sodium hydroxide 6.68 Mass product produced 3.2994 + NaOH heat, L + H20 3-bromo-3-ethylpentane is a neat liquid. It is reacted with an aqueous sodium hydroxide solution and heated. The product 3-ethyl-2-pentane product is a liquid. 3-bromo-3- sodium hydroxide 3-ethyl-2-pentene ethylpentane Density (g/mL) 1.138 Mol. Wt. (g/mol) 98.19 Molarity (M) 5.0 Showing full dimensional analysis, show the amount of product that could be made in grams based on your assigned volume of 3-bromo-3-pentane. Include all units and identifiers and use correct significant figures. (3 pts) Showing full dimensional analysis, show the amount of product that could be made in grams based on your assigned volume of sodium hydroxide solution. Include all units and identifiers and use correct significant figures. (3 pts) What is the maximum amount of product which may form? (1 pt) What is the limiting reagent? L(Ipt) Show calculation for determining the percent yield. Use correct significant figures. (2 pt)

Answer 1

1) Starting volume of 3-bromo-3-ethylpentane = 4.77mL Mass of 3-bromo-3-ethylpentane = volume * density = 4.77*1.138 = 5.43 g Number of moles of 3-bromo-3-ethylpentane = mass / molar mass = 5.43/179 = 30.3*10^-3 moles With respect to these number of moles; Expected theoretical numnber of moles of product = 30.3*10^-3 moles expected theoretical mass of product=molar mass*mole = 98.2*30.3*10^-3 = 2.98 g 2) Number of moles of NaOH = 5.Omol/1000mL*6.68mL = 33.4*10^-3 moles With respect to these number of moles; Expected theoretical numnber of moles of product = 33.4*10^-3 moles expected theoretical mass of product=molar mass*mole = 98.2*33.4*10^-3 = 3.28 g 3) The limiting reagent is 3-bromo-3-ethylpentane, hence maximum amount of product may form is = 2.98 g 4) The limiting reagent (or limiting reactant or limiting agent) in a chemical reaction is the substance that is totally consumed when the chemical reaction is complete.

5) % yield = (Actual yield/theoretical yield)* 100 = (3.294/2.98)*100 = 111% This could be because you may have obtained crud product mass.