WorksheetsChemistry 1 (2)
Total questions: 9
Worksheet time: 1hrs 25mins
50,0 grams of solid NaOH was added into 1,50 L of 2.40 M NaOH and stirred gently. Water was added into solution until the volume of solution reach 5,00 L. Determine final concentration of NaOH in the final solution (Ar Na = 23 g/mol; Ar O = 16 g/mol, Ar H = 1 g/mol)
3.6 M
1.24 N
0.97 M
6.3 ppm
5 % w/v
0,1 moles of HI added into 1 L of container and dissociated according to reaction below at 450 °C :
2HI -----> H2 + I2
At equilibrium, 0.02 moles of I2 was formed, evaluate K for the reaction at 450 °C
6.01
2.12
1.67
0.27
0.10
The gas-phase decomposition of NOBr is second order in [NOBr], with k = 0.810 M-1s-1 at 10°C. We start with 2.40 x 10-3 M NOBr in a flask at 10°C, what concentration of NOBr will remain after 5.00 minutes of reaction?
2NOBr(g) ---> 2NO(g) + Br2(g) rate = k[NOBr]2
9.26 x 10-4 M
1.11 x 10-3 M
2.13 x 10-4 M
2.26 x 10-3 M
1.29 x 10-3 M
Sucrose is a nonvolatile, nonionizing solute in water. Determine the vapor pressure lowering,
at 25°C, of the 1.25 m sucrose (made from 50.0 grams of sucrose and 117 grams of water). Assume that the solution behaves ideally. The vapor pressure of pure water at 25°C is 23.8 torr.
1.432 atm
0.00124 torr
2.671 mmHg
0.00069 atm
0.245 torr
A 50.0-mL sample of 0.400 M copper(II) sulfate solution at 23.35°C is mixed with 50.0 mL of 0.600 M sodium hydroxide solution, also at 23.35°C, in the coffee-cup calorimeter. After the reaction occurs, the temperature of the resulting mixture is measured to be 25.23°C. The density of the final solution is 1.02 g/mL. Calculate the amount of heat evolved. Assume that the specific heat of the solution is the same as that of pure water, 4.184 J/g°C.
CuSO4(aq) + 2NaOH(aq) ---> Cu(OH)2(s) + Na2SO4(aq)
846 J
432 J
1692 kJ
0.0461 J
0.196 kJ
What volume of oxygen gas (measured at STP) is produced by the oxidation of water in the electrolysis of copper(II) sulfate during the passage of 2.50 amperes of current through a solution of copper(II) sulfate for 50.0 minutes!
0.435 L
1.534 L
0.761 L
0.879 L
0.242 L
Which following statement is TRUE about cell diagram of Co/Co2+//Ni2+/Ni dan Cu/Cu2+//Ag+/Ag.
Supporting data:
Eo Co2+;Co = – 0,28 volt; Eo Ni2+;Ni = – 0,25 volt
Eo Cu2+;Cu = + 0,34 volt; Eo Ag+;Ag = + 0,80 volt
Oxidation : Ag ---> Ag+ + e
Reduction : Cu2+ + 2e ---> Cu
E0sel = 0.64 V
Oxidation : Cu ---> Cu2+ + 2e
Reductioni : Ag+ + e ---> Ag
E0sel = -0.46 V
Oxidation : Co ---> Co2+ + 2e
Reduction : Ag+ + e ---> Ag
E0sel = -1.08 V
Oxidation : Ni ---> Ni2+ + 2e
Reduction : Co2+ + 2e ---> Co
E0sel = 0.53 V
Oxidation : Co ---> Co2+ + 2e
Reduction : Ni2+ + 2e ---> Ni
E0sel = 0.03 V
Use the following initial rate data to determine the form of the rate-law expression for the reaction
3A + 2B ---> 2C + D
rate = 6x105[A]3[B]
rate = 3x105[A]3[B]2
rate = 5x103[A][B]
rate = 4.3x105[A][B]3
rate = 1x105[A]2[B]
Potential of electrochemistrycell can be used to determine the equilibrium constant of very dilute solution. Evaluate the value of K from the equilibrium reacton below.
3Zn(s) + 2Cr3+(aq) → 3Zn(aq) + Cr(s) E°sel= +0.0218 V
K = 13.2
K = 19.3
K = 162
K = 123
K =129
