Chemistry Answers

How much heat is released when 358 g of water cools from 68.3°C to 18.9°C? The specific heat of water is 4.184 J/g°C.

The average diameter of an adult human eyeball is 24mm. What is the diameter in dm?

How many hydrogen atoms are in 2.50 g of pharmacolite,

CaHAsO4•2H2O (M = 216.0)?

1. Constraints on the number of independently moving particles; i.e., on whether the particles must move as an aggregate or can move separately.

2. Constraints on the direction of motion.

3. Constraints on the volume in which the motion is executed

How thermodynamic properties, in particular Entropy, would now respond to these constraints.

1. The osmotic pressure of 250mL of an aqueous solution containing 0.150g of the enzyme lysozyme is found to be 0.0013atm at 24.85⁰ Calculate the molar mass of lysozyme.

1. How many grams of Lactic acid (C₆H₁₀O₅) should be dissolved in 650g of cyclohexane (C₆H₁₂) to raise the boiling point to 84.91⁰C? The normal boiling point of cyclohexane is 81⁰C and its molal boiling point is 2.75 ⁰C/m.

1. You add 1 kg of ethylene glycol (C₂H₆O₂) antifreeze to 4500g of H₂O in your car’s radiator. What would be the freezing point of the solution?

1. A solution prepared by adding 10g of an unknown non-volatile, non-electrolyte solute to 150 g of water. The Boiling point of the solution is elevated by 0.433 ⁰C above the normal boiling point of the solvent. What is the molar mass of the unknown substance?

1. What is the vapor pressure of the pure solvent if the vapor pressure of a solution of 15g sucrose (C₁₂H₂₂O₁₁) in 100g of ethanol (C₂H₅OH) is 58 mmHg?

1.  mL of nitric acid, HNO₃, are required to react with 50 mL of a 1.25 M Barium hydroxide, Ba(OH)₂ solution:

2 HNO_3 (aq)           +      Ba(OH)_{2 (aq)} -->    2 H₂O _(aq)    +      Ba(NO₃)_{2 (aq)}

Determine the concentration (Molarity) of the nitric acid solution (HNO₃).