Choose the reaction that illustrates Hf for Ca(NO3)2. A) Ca(s) ...

[jwb375]

Choose the reaction that illustrates Hf for Ca(NO3)2.
 
  A) Ca(s) + N2(g) + 3O2(g)  Ca(NO3)2(s)
  B) Ca2+(aq) + 2 NO3-(aq)  Ca(NO3)2(aq)
  C) Ca(s) + 2 N(g) + 6 O(g)  Ca(NO3)2(s)
  D) Ca(NO3)2(aq)  Ca2+(aq) + 2 NO3-(aq)
  E) Ca(NO3)2(s)  Ca(s) + N2(g) + 3O2(g)

Question 2

How would the concentration change if a 1.0 L flask of 1.0 M NaCl were left uncapped on a laboratory bench for several days. Why?
 
  What will be an ideal response?

[Pariscourtney]

Answer to Question 1

A

Answer to Question 2

The concentration would slowly increase as water from the solution evaporated. This is because the amount of NaCl in the flask would remain constant while the amount of water decreases.

[jwb375]

Thanks for the timely response, appreciate it

[rachel]

Excellent