Chemistry Answers

A wooden object found in an Indian burial ground and subjected to radiocarbon dating. The decay rate associated with C- 14 is l0 disintegrations per minute per gram carbon. What is the age of the object?

What pressure is required to reduce 64 mL of a gas at standard conditions to 17 mL at a temperature of 29◦C? Answer in units of atm.

What are the freezing point and boiling point of a solution that contains 5 g of glycerol (C₃H₈O₃) and 20 ml of water. 

Assuming Raoult’s law applies, calculate the vapor pressure of a solution of 45 g of glucose (C₆H₁₂O₆) in 95 g of water at 25 degrees Celsius

Sphere A and B have the same initial positive charge q0. The magnitude of the repulsive electric force between the two spheres is 14.1 N when separated by a distance of 0.03 m. (a) find the initial charge q0. (b) The spheres are then allowed to touch each other and the separated. Find the electric force between them if the radius of sphere A is there times that of sphere B.

Predict the atomic radius of antimony given the radius of arsenic (0.125nm) and bismuth (0.155nm)

Two different atoms have four protons each and the same mass. However , one has a positive charge while the other is neutral. Describe what each atomic structure could be, listing the possible number and location of all subatomic particles.

chemist carries out a reaction that generates several side products. Which of the following can she eliminate from the reaction mixture by washing with an aqueous solution of sodium hydroxide?

100.0 mL of a 0.500 M solution of KBr is diluted to 500.0 mL. What is the new concentration of the solution?

5.Balance the equation below and use it to answer the questions that follow:

C₂O₄^2-(aq) + MnO₄^-(aq) + H⁺(aq) = CO₂(g) + Mn²⁺(aq) + H₂O(I)

(I) Which ionic species is an oxidizing agent and which is a reducing agent

(II) Twenty five 25 cm³ of a solution of sodium ethanediote of concentration 0.1 mol dm^-3 were placed in a conical flask. A burrete was filled with patassium manganate (VII) solution of concentration 0.038 mol dm^-3 . Determine the volume of the manganate (VII) solution that would be needed to give the endpoint in the titration.

(III) Assuming that the KMnO₄ was prepared by dissolving 6.94 g of salt in 1 dm³ of solution. Calculate the % purity of KMnO₄