Chemistry Answers

Several physicochemical parameters vary with temperature. For example, at 100°C the pH of pure water is approximately 6. Under these conditions. Calculate the concentration of OH- in micromolar.

Poly(methyl methacrylate) is used in the manufacture of resins and plastics. The green synthesis is shown below. Determine the atom economy for the process.

The chemical X has an LD5o of 80 mg/kg. The lethal dose is expressed as the milligrams of X (80 mg) per kilogram of body weight of the test animal (typically rats ). This dose tell s us that 50% of the rats will die if they are given 80 mg of X per kg body weight of the subject animal. Thus, for a person who weighs 100 kg there is a 50% chance that a dose of (80 mg) x (70 kg) = 5600 mg or 5.6 g may be fatal. What is the volume of X (in microlitres) for the fatal dose (LDso) of X that will kill a person who weighs 70 kg? (Density of X = 1.446 g/mL).

A 50.00 mL water sample is titrated to the phenolphthalein end-point with 5.00 mL of 0.02 N H2S0 4 , and to the methyl orange end-point with additional 5.00 mL of the acid. What is the total alkalinity, in mgCaC03 /L?

49.85 grams of solid silver carbonate is dissolved in the calorimeter and the temperature goes from 23.15∘

C to 10.01∘

C g What is the ∆H for the solution process? The heat capacity of calorimeter and its contents is 311 

Differentiate between integral enthalpy of so;ution and differential enthalpy of solution.

The Ksp for calcium hydroxide is 5.02 x 10-6 at 25°C. Calculate the concentrations

of calcium ions and hydroxide ions in a saturated aqueous solution of calcium

hydroxide.

Determine the solubility of calcium hydroxide in molL-1 and gL-1 (0.01-0.10 molL-1 is

classified as sparingly soluble).

The solubility of magnesium carbonate is 0.0220g in 100ml. Determine the

solubility product.

0.50g of Ca(OH)2 in 1000ml water at 25°C.