Ch. 10, 14, & 19 thermodynamics & nuclear chem 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. What information can be provided by: [9 points]
a. ∆ H
b. ∆ S
c. ∆ G
2. What does the equation: E = m c 2 mean ? [6 points]
3. What is ∆ S reaction: mix aqueous solutions of sodium phosphate and calcium chloride ? Justify your answer. [15 points]
4. KOH (s) --> K +(aq) + OH -(aq) [15 points]
a. calculate ∆ H of the above reaction.
b. what is the amount of heat generated or consumed in the above reaction by dissolving 2.0 g solid KOH in water ?
c. what is the temperature of 45 g water at 25 °C, when 2.0 solid KOH was dissolved in water ?
5. write the nuclear reaction described below: [20 points]
a. 95Kr undergoes beta minus decay: _______________________
b. 80Rb undergoes beta plus decay: ________________________
c. 187Hg undergoes alpha decay: ________________________
d. 238Np --> 2 10n + 95 Nb + _____
e. 4He + 11B --> __________
6. 35S has a half-life of 87 days. [15 points]
a. what is the decay constant of the isotope ?
b. 100. g 35S decays to 10.0 g 35S. What is the age of the object ?
c. how much time would it take for 250. g 35S to become 50.0 g 35S ?