HO - iN

CH,N, Et,0, CH,Cl, 30 min HO,

CH₂-COOH Citric acid has the formula HO-C-COOH I CH₂-COOH CH2–CDD - Na* + HD-C-CDD- Na CH₂-COO- COO-Na A 25.0 mL sample of a concentrated citrus fruit cordial component (e.g. for lime juice), used in the food & drinks industry, was diluted to 250 mL in a graduated volumetric flask. A 25.0 mL sample of this diluted solution, required, on average, 22.5 mL of a standard 0.100 molar sodium hydroxide solution using phenolphthalein indicator for the titration end-point. A) 0.0075 Assuming all the acid in the cordial was citric acid, calculate the concentration of the acid in g/mL in the original solution. B) 0.576 D and is tribasic acid, forming the tri-sodium salt on complete neutralisation with sodium hydroxide. 1.44 0.00225

+ 1.03 2. Me₂S od c B A LOH

K An oil company needs to fill orders for 91-octane gas, but only has 88- and 92-octane gas on hand. The octane rating is the percentage of isooctane in the standard fuel. How many liters of 88-octane gas should be mixed with 300 liters of 92-octane gasoline to get a mixture that is 91-octane gas? Let x be the amount of 88-octane gas used in the mixture. Complete the following chart. Type of Gas 88-octane 92-octane Mixture Quantity X 300 x+300 % Isooctane 88% 92% 91% Amount of Isooctane 0.91 (Simplify your answers. Use integers or decimals for any numbers in the expression.)

The following chemical reaction is an/a    _______ reaction? 2C2H5OH(l) + 7O2(g) → 4CO2(g)+ 6H2O(g)+ 654 kcal Exothermic or endothermic?

b) HO OH

Br 01 HNMe2 SN1 SN2 E1 E2 No Reaction

Br SH Heat El

Copper can be drawn into thin wires. How many meters of 34–gauge wire (diameter=6.304 × 10 in) can be produced from the copper in 5.00 lb of covellite, an ore of copper that is 66.0% copper by mass? (Hint: Treat the wire as a cylinder: Vof cylinder = arh; d of copper=8.95 g/cm*). %3D !!