What are the respective concentrations (M) of K+ and PO43- ...

[jho37]

What are the respective concentrations (M) of K+ and PO43- afforded by dissolving 0.800 mol K3PO4 in water and diluting to 1.63 L?
 
  A) 0.800 and 0.800
  B) 0.491 and 0.491
  C) 0.800 and 0.491
  D) 1.44 and 0.491
  E) 0.489 and 0.163

Question 2

In the electrochemical cell using the redox reaction below, the cathode half-reaction is ________. 2H+ (s) + Sn (s)  Sn2+ (aq) + H2 (g)
 
  A) 2H+ + 2e  H2
  B) Sn  Sn2+ + 2e
  C) 2H+  H2 + 2e
  D) Sn + 2e  Sn2+
  E) Sn + 2e  H2

Question 3

At constant pressure, the combustion of 15.0 g of C2H6(g) releases 777 kJ of heat. What is H for the reaction given below? 2 C2H6(g) + 7 O2(g)  4 CO2(g) + 6 H2O(l).
 
  A) -129 kJ
  B) -779 kJ
  C) -1560 kJ
  D) -3108 kJ

Question 4

How many anions are in 0.500 g of MgBr2?
 
  A) 1.64  1021 anions
  B) 3.27  1021 anions
  C) 2.22  1026 anions
  D) 4.43  1026 anions

[lucas dlamini]

Answer to Question 1

D

Answer to Question 2

A

Answer to Question 3

D

Answer to Question 4

B

[jho37]

Great answer, keep it coming

[Liddy]

Wow, this really help