Ch. 13, 15 gas & solution test [80 points] Honors Chemistry

Show your work in an organized manner, includes any relevant equation / formula, proper units in your work / answer, and the proper number of significant figures in your answer.

1. solve for the unknown pressure. [15 points]

	Initial	Final
pressure	500. torr	?
volume	750. mL	2.0 L
temperature	20. °C	400. K

2. A container at STP has 4.0 g H₂, 40. g O₂, and 60. g N₂. What is the partial pressure of O₂ ? [10 points]

3. H₂O_{2 (aq)} --> H₂O _(l) + O _{2 (g)}

How many grams of H₂O₂ would decompose if there was 5.0 L O₂ at 25 °C and 1.0 atm formed in the above reaction ? [15 points]

4. Na₂CO_{3 (aq)} + FeCl_{3 (aq)}  -->  ___ grams of a precipitate. [15 points]

100. mL           50. mL

200. mM         300. mM

5. Describe how to prepare 275 mL of 10.0 mM glucose using 25 mM glucose, C₆H₁₂O₆. [10 points]

6. 1.0 g nonelectrolyte dissolved in 10.0 benzene (C₆H₆) has a boiling point of 83.0 °C. What is the molar mass of the nonelectrolyte ? [the boiling point of benzene is 80.1 °C and its K_b is 2.5 °C / molal; 15 points]