Important Events Of Soccer

-1 º Bachillerato

1

PROBLEMS
Solutions

1. What
   _{amount of ZnCl 2} needed to prepare
   3L 0.32 M solution? Atomic masses: Zn = 65.3 u; Cl = 35.5 u.
   Sun: 130.84 g.

   
   

2. 7g is
   KCl dissolved in 51g of water. What is the concentration of this solution
   in% by mass? Sun:
   12'07%.

   
   

3. 
   How many grams of NaOH are there in 50cm 3 0'6M
   dissolution of it? Na = 23U, H = 1u, O = 16U. Sun: 1'2g

   
   

4. 
   is a solution prepared by mixing 90g water and 92g of ethyl alcohol
   CH 3 CH 2 OH. Find:
   a) proximate concentration of alcohol in water, b) moles of alcohol
   c) molality of the solution if the alcohol is the solute
   . Sun: 50'55%, 2 moles; 22'2 molal.

   
   

5. 
   Calculate the grams of glucose (C 6 _{H 12 O} 6)
   that must be dissolved in water 200g
   to prepare a 0.2 molal solution. Sun: 7.2 g.

   
   

6. 
   It has a nickel sulfate solution (II) to
   6% by mass. Calculate the molarity of this solution
   knowing its density is 1.06 g / mL. Ni = 58.5 u; S = 32U, O = 16U Sun: 0.41 M.

   
   

7. 
   Calculate the molarity, normality, molality and mole fraction of solute
   an aqueous solution
   nitric acid to 33.50% by mass and density 1.2 g / mL. Sun: 6.38 M, 6.38 N, 8mm, 0.126.

   
   

8. 
   have a solution _{2N H 2 S} density 0.95 g / mL. Halla
   concentration: g / L, molarity,% by mass, molality
   , Xs and Xd. Sun: 34g / L, 1M, 3.58%, 1.09 molal, 0.02 and 0.98.
   

   
   

9. 
   Calculate the concentration in mass%
   a solution of ethyl alcohol (CH 3 ₂ CH OH) in water, knowing that
   Xs = 0.207. Atomic mass C = 12u, O = 16U, H = 1u.
   Sun: 40%

   
   

10. We
    5M solution of sodium sulfate and 250mL
    want to prepare for another that is 75% and density 0.75 g / mL. a) What volume of solution
    5M we take?; B) How
    the prepare yourself? Na atomic mass = 23, S = 32 O = 16.
    Sun: 198mL.

    
    

11. The
    commercial sulfuric acid has a density of
    1.84 g / mL and a concentration of 18.1 M. a) Calculate his wealth
    in percent by mass; b) How many mL of the solution above
    will be needed to prepare 2L
    0.4 N solution? Sun: 96.4%, 22.1 mL.

    
    

colligative properties of solutions:

12. The radiator
    a car contains 6L water and supplemented with 4kg
    _{glycol CH 2 OH-CH} 2 OH (M = 62U).
    want to know the temperature at which freeze the mixture. Kc = 1.86. Sun:
    -20 º C.

    
    

13. 
    A solution containing 4.5 g of a substance in water 125g
    frozen at - 0.372 ° C. Calculated molecular mass of solute
    . Kc = 1.86. Sun: 180u

    
    

14. 
    Calculate the freezing temperature of a solution
    produced by dissolving 10 g of sucrose (M = 342u) in 500 g of water.
    Kc = 1.86. Sun:  0.11 º C
    

    
    

15. The
    Nicotine is a compound of formula empirical
    (C 5 H 7 N) n. Find its molecular formula
    knowing that
    dissolve 0.5 g of the substance in 12g of water, the resulting solution
    boils at 100.14 ° C at normal pressure. Ke = 0.52. C = 12u, 14u
    N =, H = 1u Sun: C _{10 H 14 N} 2.

    
    

16. mix is \u200b\u200b
    ^{150cm 3} of hydroxide solution 2M Sodium
    with 50cm 3 other
    0.5 M solution of the base. Follows the molarity of the resulting solution.
    Sun: 1.625 M.

    
    

STOICHIOMETRY

17. In the combustion of 42
    
    g carbon dioxide occurs. What volume in CN
    oxygen and air are needed? What
    amount of carbon dioxide is obtained?
    Air has a 21% oxygen. Atomic weights C = 12u, O = 16U. Sun:
    78.4 L of oxygen, air 373'3L; 154g CO 2 .

    
    

18. Al
    heating potassium chlorate gets oxygen and potassium chloride
    . a) Calculate the grams of potassium chlorate needed
    for oxygen 2L in normal conditions;
    c) How many grams of potassium chloride have been found?
    d) What kind of reaction is? Data:
    atomic mass-cas: Cl = 35'5u; K = 39u, O = 16U. Sun: b)
    7'29 g of KClO 3 c) 4'43 g of KCl, d)
    decomposition.
    

    
    

19. 
    Find the volume of air that cn needed for combustion
    total of 1 kg of coal for 84% of wealth in coal.
    What volume of carbon dioxide at 127 º C and 760 mm pressure
    has occurred? The air is 21% oxygen
    . Sun: 7466.67 L air;
    _{2296L CO 2} .

    
    

20. Halla
    the purity of a sample containing ammonium sulfate, knowing that if taken
    13'61 g and treated with excess caustic soda
    3'82 liters of ammonia off
    measured at 18 ° C and 745 mm of mercury. Atomic mass S = 32U;
    O = 16U; N = 14u; H = 1u. Sun : 76%.

    
    

21. 10g is
    reacted aluminum oxide with excess hydrochloric acid and obtained
    25g of aluminum chloride .
    estimated yield of the reaction. Atomic masses: Al = 27U;
    O = 16U and Cl = 35.5 u. Sun: 95.5%

    
    

22. The
    reaction between sodium chloride and silver nitrate gives rise to chloride
    silver and sodium nitrate. Assuming that the reaction takes place
    a yield of 65% and we want to obtain 80.04 g
    silver chloride, a) what
    amount of sodium chloride is required? b) What if
    sodium chloride were of a purity of 20%. M: atomic mass:
    Na = 23U; Cl = 35'5u and Ag = 108u, Sun : a) 50'2
    g NaCl, b) 251 g of sample

    
    

23. 
    How many grams of sulfuric acid 90% of wealth
    need to obtain 1 kg of calcium sulfate by reaction
    with slaked lime Ca (OH ) ₂ ? S = 32U atomic masses,
    Ca = 40U, H = O = 1U and 16U. Sun: 800'65 g.

    
    

24. Al
    add calcium hydride occurs on water and calcium hydroxide
    shows a gas. a) Write the reaction that takes place
    . b) Calculate the grams of calcium hydride of 87% purity
    that would be required for 2000 L of gas at 25 °
    C and 720 mm Hg. M. atomic H = 1u, Ca = 40U. Sun: 1871.55 g
    _{CaH 2} .

    
    

25. 
    Calculate the grams of calcium carbide (CaC 2 ) that
    can be obtained from calcium oxide, with 1000 g of carbon 90% of wealth
    if the reaction yield is 70%.
    What volume of carbon dioxide is obtained
    CN? Atomic masses: C = 12u, Ca = 40U. Sun: 1344 g;
    235.2 L.

    
    

26. Find
    the volume of gaseous hydrochloric acid is
    cn obtained by reacting with sulfuric acid
    a sample of 500 g of salt formed in 30% potassium chloride and 70% of
    sodium chloride. Data: atomic masses: Cl = 35'5u;
    Na = 23U; K = 39u. Sun: 179.12 liters.
    

    
    

27. 
    A 1g sample consisting of sodium carbonate and potassium carbonate
    , treated with acid hydrochloric
    get a mixture of 1.092 g sodium chloride and potassium chloride.
    Calculate the initial mixture composition in per cent of each component
    . Atomic masses: Na = 23U, C = 12u;
    O = 16U; Cl = 35.5 u; K = 39u. Sun: 50% of each.
    

    
    

28. What
    sulfuric acid may be obtained from 100g
    pyrite. The reactions are unadjusted:
    FeS 2 + O 2  Fe 2 _{O 3 + SO}
    2, SO 2 _{+ O 2 } SO ₃ ;
    _{SO 3 + H} 2 O  _{H 2 SO} 4.
    atomic masses and Fe S = 32U = 56U. Sun : 163.3 g.

    
    

29. The hydrochloric acid
    reacts with silver nitrate
    forming silver chloride and nitric acid.
    Calculate the grams of silver chloride to be formed if
    react completely 25mL of hydrochloric acid solution 2M
    . Atomic mass: Ag = 108u, Cl = 35.5 u.
    Sun: 7.175 g.

    
    

30. 
    reacted was 12 g calcium carbonate
    with excess hydrochloric acid. Calculate: a) The volume of CO
    2 at 20 ° C and 0.9 atmospheres.
    b) The amount of calcium chloride obtained. c) The volume of HCl solution
    16% by mass and density 1.25 g / mL
    be used. d) What kind of reaction
    belong? Data: atomic masses: Ca = 40U; O = 16U, C = 12u;
    Cl = 35.5 u. Sun: a) 3'2 l; b) 13'32 g.
    c) 43.8 mL.

    
    

31. For
    reaction of zinc with AC. hydrochloric
    get zinc and hydrogen chloride. a) What kind of reaction
    is it? b) What volume of hydrochloric acid
    55% by mass and density 1.5 g / mL,
    must react with an excess of zinc to produce
    50L of hydrogen, measured at 32 º C and 760mm Hg. Atomic masses:
    S = 32U; O = 16U, H = 1u. Sun: 177 mL

    
    

32. In
    a flask of 1 liter of oxygen is 0.05 moles and 0.05 moles of hydrogen
    . A spark is produced
    and liquid water. Calculate: a) The moles of water formed, b)
    How many moles of gas remain without reacting? c) What
    is the pressure inside the flask at 0 ° C? d) Indicates the type of reaction
    . Sun:
    a) 0.05 moles of water; b) 0.025 moles; c) 0'56
    atmospheres.
    

    
    

33. 
    is reacted a mixture of 48g of S and 78.4 g of Fe to produce iron sulfide
    (II) Indicates a) Is there any
    excess reagent?, b) How many grams of ferrous sulphide will
    ? Atomic mass data S = 32U; Fe = 56U. Sun :
    a) Excess of 3.2 g of sulfur., B) 123'2 g FeS.

    
    

34. burning desire is
    78.4 L of methane gas CH 4 CN, using 200g
    oxygen. The reaction produces carbon dioxide and water
    . A) Which reactant is in excess moles
    and how many left? B) Calculate the grams of carbon dioxide
    to be obtained. Atomic masses: C = 12u;
    O = 16U. Sun: 137.5 g 0.375 moles

    
    

burn Al
0'42 g of an oil is produced _{1'32 g of CO 2}
and 0,54 g water. If the density relative to air is 1.45, calculated
molecular formula. (Hint:
average molecular mass of air = 28'8 u) (Sun: C _{3 H} 6)

In the fuel
n of 0'785 g
an organic compound formed by C, H and O, are obtained _{1'5g CO 2 and}
0'921 g of water. To vaporize 0'206 g of compound 108 is evicted
mL of air measured over water at 14 º C and 756 mm Hg
. Find the molecular formula of the compound. (Hint:
vapor pressure of water at 14 º C is 12 mm Hg) (Sol (C H 2 O 6).

By analyzing an organic compound results:
40'7% C; 5.1% and 54'2% H O.
solution formed by 11.8 g of compost and 200 mL of water freezes at 93 º C.
-0 Find its molecular formula. (Soln: 4
C 6 H _O 4)