General Chemistry Answers

Find the molar mass of a substance with 0.58 gram of compound value (X) in 0.23 mol number of moles (X).

Calculate the freezing and boiling point of a solution prepared by dissolving 32.60 g of ferric chloride (FeCl3) in 0.4 m3 of water (H2O).

H2 and F2 react to form HF:

H2 (g) + F2 (g) → 2 HF (g)

the relevant bond dissociation energies, in kJ/mol, are: 

H—H: 436 F—F: 155 H—F: 567

Showing your work, calculate the value of ∆H for this reaction. Is this exothermic or endothermic?

A hypothetical reaction to form the compound A3B2 from its constituent elements is shown 

below. 

A2 (g) + B2 (g) → A3B2 (l) ∆H = –13.4 kJ/mol AB3 ∆S = –84.3 J/mol∙K 

Calculate the change in free energy (∆G) for this reaction at 298 K (25 °C, “room temperature”) using the formula ∆G = ∆H - T∆S. 

C2H2 (g) + 2 H2 (g) → C2H6 (g) + 42 kcal

a. Is this reaction exothermic or endothermic? Briefly explain your choice.

b. Would you expect entropy to increase or decrease for this reaction? Briefly explain.

Calculate the amount of heat released during the combustion of

a. 0.75 mole of C3H6O

b. 120g of C3H6O

If 1 more of O₂ react with 1 mole of N₂ - how many moles of NO₂ can be formed?

Verify the following chemical equation is balanced

TiO₂ + 2C → Ti + 2CO

If you begin with 15.9 kilograms of carbon, how many moles of Ti can be produced?

1. In the winemaking industry, laboratory procedures are employed in determining the right concentration of wine for safety purposes. For example, to analyze the alcohol content of a certain wine, a chemist needs 1.00L of an aqueous 0.200 M K2Cr2O7 (potassium dichromate) solution. How much solid K2Cr2O7 must be weighed out to make this solution?

Which of the following correctly determines the mole fraction of 250. g sucrose (MM = 342 g/mol) dissolved in 1000mL of water?