Other Chemistry Answers

   A 2.00 g sample of an iron ore is dissolved in acid and then reduced to Fe²⁺. It was then titrated against 0.025 M KMnO₄ solution and used 47.5 mL to reach the end point. Calculate the %Fe₃O₄ (231.54 g/mol) of the ore sample.

  A 2.00 g sample of an iron ore is dissolved in acid and then reduced to Fe²⁺. It was then titrated against 0.025 M KMnO₄ solution and used 47.5 mL to reach the end point. Calculate the %Fe₃O₄ (231.54 g/mol) of the ore sample.

The end point in a titration of a 50.00 mL sample of HCl solution was reached by the addition of 35.23 mL of 0.250 M NaOH. What is the molarity of the HCl sample?

Hydrogen is prepared commercially by the reaction of methane and water vapor at elevated temperatures.

CH₄ (g) + H₂O (g) ⇌ H₂ (g) + CO (g)

What is the equilibrium constant for the reaction if a mixture at equilibrium contains gases with the following concentrations, at a temperature of 760 °C?

CH₄ = 0.126 M

H₂O = 0.242 M

CO = 0.126 M

H₂ = 1.15 M

4. A combustion reaction wherein 15.0 g of propane (C3H8) is burned with 75.0 g of oxygen (O2).

a. Determine the limiting reactant.

b. What is the maximum amount of CO2 (g) can you produce?.

What is the concentration of NaCl in a solution if titration of 15.00 mL of the solution with 0.2503 M AgNO3 requires 20.22 mL of the AgNO3 solution to reach the end point?

AgNO3 (aq) + NaCl (aq) ⟶ AgCl (s) + NaNO3 (aq)

1.     How do you prepare a 250-mL of 0.125 M NaOH solution? Show your calculations and the methods/steps needed to prepare the solution.

a.      From solid NaOH pellets (by dissolving)

[Calculate the moles needed and convert it to grams]

b.     From a solution of 0.745 M NaOH (by dilution)

How do you prepare a 250-mL of 0.125 M NaOH solution? Show your calculations and the methods/steps needed to prepare the solution.

a. From solid NaOH pellets (by dissolving)

[Calculate the moles needed and convert it to grams]

b. From a solution of 0.745 M NaOH (by dilution)

1. Xiangling, a chef from Liyue weighed ten prawn samples from a batch of prawn delivery for her restaurant. Based on these data determine the different statistical parameter asked

[You may use the stat function or spreadsheet to calculate the values for mean and standard deviation. Just show your solutions for the values of Qexp and Gexp and your conclusion.]

Prawn 1 51.56 g Prawn 6 54.03

Prawn 2 53.01 g Prawn 7 53.90

Prawn 3 57.89 g Prawn 8 53.51

Prawn 4 52.97 g Prawn 9 52.95

Prawn 5 53.56 g Prawn 10 53.24

a. Determine an outlier using Q-test (95.0% confidence)

b. Determine an outlier using Grubb’s Test (95.0% confidence)