Balancing Synthesis and Chemical Equations: Chemistry questions&Answers (4(NH4)2MoO4 + 16 H3SiCl + 8 NH3 --> 2 Mo(NH)2Cl2(NH3)2 + 4 H6Si20 + 8 N H4Cl)

 

Chemistry questions

1.      Balance the following synthesis reaction using whole number coefficients (not fractions):
4(NH₄)₂MoO₄ + 16 H₃SiCl + 8 NH₃ --> 2 Mo(NH)2Cl2(NH3)2 + 4 H6Si20 + 8 N H4Cl

Answer:

Balanced equation: (NH4)2MoO4 + 8 H3SiCl + 8 NH3 = Mo(NH)2Cl2(NH3)2 + 4 H6Si2O + 6 NH4Cl

2.       For the reaction between Na2S + Sn(CI04)4 write out the following, including physical states and charges where appropriate:

a)      the balanced equation

     Sn (ClO4)4 + 2Na2S → SnS2 + 4NaClO4       

b)      complete ionic equation

Sn⁺ +Cl^- +O₄ + 2Na⁺ +2S- → SnS2 + 4Na ⁺+Cl- +O₄

c)       net-ionic equation

Sn⁺ +2S^- → SnS2

3.     For the reaction between Al2 (CO3)3 + HNO3 write out the following, including physical states and charges where appropriate:

a)      Balanced equation

Al₂ (CO3)3 + 6HNO3 → 3CO2 + 3H2O + 2Al (NO3)3       

       b) Complete ionic equation

2Al^3- (aq) + 6NO^3- (aq) + 6Na- (aq) + 3CO₃ ^2- (aq) → Al₂ (CO3)3(s) + 6Na⁺ (aq) + 6NO^3- (aq)

c)       net-ionic equation

2Al 3- (aq) + 3CO3 2- (aq) → Al2 (CO3)3(s)

Based on the unbalanced reaction: OsO4 + Mn2+ --> Os + MnO4-

The balancing coefficients are:

0s04 = 2

Mn2+ = 1

Os = 2

Mn04- = 2

5.      Based on the unbalanced reaction: O_sO₄ + Mn2+ --> O_s + MnO4-
The balancing coefficients are:

H+ = 1

 H20 =1

6.      What are the concentrations of Hg22-E and C2H302- ions at the end of the reaction between Hg2 (C2H302)2 and CrBr3?

Hg2²⁺ = 560.988 M

C₂H₃O₂- = 229.128 M

7.       What are the concentrations of Cr3+ and Br- ions at the end of the reaction between Hg₂(C2H302)2 and CrBr3?

Cr3+ = 0.519 M

Br- = 0.275 M

8.       You have collected a mixture of CO2(g) and CO(g) in a sealed 1.50 L flask containing water with a total pressure of 766 mmHg and a temperature of 50.0 °C. If there is twice as many moles of CO as CO2, what are the mole fractions of each gas, the partial pressure of CO2 and the number of moles of CO2?

Vapor Pressure of H20(0

PH20, 17.5 31.8 55.3 92.5 149.4 mmHg T, °C 20.0 30.0 40.0 50.0 60.0

XCO2 = 0.423 Xco = 0.293 PCO2 = 224 mm Hg nco2 = 0.0241 moles

Answer 1: 0.423 Answer 2: 0.293 Answer 3: 224 mm Hg

Answer 4: 0.0241 moles

9.       Calculate the speed of CO2 (M.W. = 44.01 g/mole) in respect to CO (M.W. = 28.00 g/mole) and determine the actual speed of CO2 at 35.0 °C.

Vc02 = 0.6362 vco

Vc02 = 417.8 m/s

Answer 1: 0.6362 Answer 2: 417.8 m/s

10.   Calculate the ideal and real temperatures of 0.289 moles of Cl2(g) contained in 10.75 L at 0.900 atm. The Van der Waals constants are a = 6.254 atmM-2, b = 0.05422 M-1.

P = [(nRT) / (V - nb)] - [(n^2 a) / (V^2)]

 n=number of moles=1.000 mol 

R=gas constant=0.08206 L-atm/mol-ºK 

T=Temp in K=100 ºC +273 ºK = 373 ºK 

V=volume of gas=1.82L 

a=6.49 L2⋅atm/mol2

b= 0.056

273K 117.9 K 408.0 K 124.4 K 409.4 K 33.48 K 4.026 K