Question

1. Refer to this equation:
   3SCl₂ + 4NaF --> SF₄ + S₂Cl₂ + 4NaCl

   
   64.0 grams SCl₂ is reacted with excess NaF and 12.5 grams of SF₄ is formed.

   What is percent yield SF₄?
   Hint: find theoretical yield
   Hint: percent yield =(actual yield/ theoretical yield) x 100

   		34.3 %
   		64.4%
   		38.0%
   		27.8 %
   		55.9 %
   		92.1%
   		36.1%
   		24.6%

2. 12.60 milliliters of a 1.25 M KOH solution are required to titrate 20.0 milliliters of a H₃PO₄ solution. What is the molarity of the H₃PO₄ solution?
   3KOH + H₃PO₄ --> K₃PO₄ + 3H₂O  

   		0.513 M
   		2.52 M
   		0.0550 M
   		0.728 M
   		3.04 M
   		0.263 M
   		1.45 M
   		0.817 M

3. 75.9 g of H ₂O at 86.0 ^oC lost ________ kJ of heat to a cooler environment.  
   The specific heat of water is 4.184 J/g·C The final temperature is 64.9 ^oC.  
   How many kJ of heat was lost?

   		18.2kJ
   		6.70 kJ
   		408 kJ
   		72.0 kJ
   		35.2 kJ

4. 63.80 grams of a metal that is at temperature 92.50 ^oC is placed in 287.0 mL of water at 21.30 ^oC.   After equilibrium, the final temperature of the water was 26.70 ^oC.   Density of water is 1.00 g/mL. Specific heat of H ₂O is 4.184 J/(g °C). What is the specific heat, c, of the metal?

   		1.54 J/goC
   		1.07 J/goC
   		1.19 J/goC
   		0.670 J/goC
   		2.90 J/goC
   		0.781 J/goC
   		0.105 J/goC
   		0.0711 J/goC

5. Consider the following thermochemical equation:                     
   3Fe₂O₃(s) + CO (g)   ->    2Fe₃O₄(s) +   CO₂(g)   ΔH _rxn =    ?
   Reaction of 18.00 g Fe₂O₃ released 1.814 kJ of heat to the surrounding. What is the enthalpy change of the reaction, ΔH _rxn?

   		-225.1 kJ/mol rxn
   		-342.1 kJ/ mol rxn
   		-7940 kJ/mol rxn
   		-303.2 kJ/mol rxn
   		-48.29 kJ/mole rxn
   		-1219 kJ/mol rxn
   		-680.2 kJ/mol rxn
   		-7518 kJ/ molrxn

6. 55.0 mL of 0.750 M MgCl ₂ solution is mixed with 110 mL of 0.750 M AgClO ₃ solution in a coffee cup calorimeter of negligible heat capacity. The initial temperature of the two solutions are both at 20.00 ^oC.   
   The final temperature of the combined solution is 27.85 ^oC .  
   How much heat did the water absorb?
   2AgClO ₃(aq) + MgCl ₂(aq) --> 2AgCl (s) + Mg(ClO ₃) ₂(aq)

   		4740 J
   		5420 J
   		1650 J
   		41.4 J
   		7.000 J
   		1030 J

Answer 1

kindly post different questions separately.