viernes, 12 de noviembre de 2010

Tarea quimica 4


                                                  Tarea química 4.
Pagina 86:
3.39-    Sn- estaño                O- 16
              SnO2                       Sn- 118
                                               Pm- 134
% elemento=   masa del elemento/ Pm  *100
% Sn=   118q/134q   * 100
% Sn= 88.06
% O= 16*2/134  * 100
%= 23.881
Sn= 88.06%
O= 23.882%

3.41-      Ca H10 O                                                              C= 12*9= 108
                                                                                              H= 10
                                                                                               O= 16
a) C= 80.597%           H= 7.463%                                        O= 11.940%
    % C= 108/134  *100
    %C= 80.597

%H = 10/134  *100                                                       %O= 16/134  *100
%H= 7.463                                                                       %O= 11.940

  3.43-       a)        C= 44.4%                                        O= 9.86%
                           H= 6.21%
                           S= 39.5%                   
1) Convertir a moles:
44.4 g 1mol c/ 12g=   3.7 mol C
6.21g    1 mol H/1g= 6.21 mol H
39.5g     1 mol S/ 32g= 1.234 mol S
9.86g    1 mol O/ 16g= 0.616 mol O
Encontrar factor común:
C= 3.7 mol C/0.616 mol= 6.006 C
H= 6.21 mol H/ 0.616 mol= 10.08 H                        =            C6 H10 S2 0
S= 1.234 mol S/ 0.616 mol= 2.003 S
O= 0.616 mol O/ 0.616 mol= 1

b)  162g/ 162g= 1               =                     C6 H S2 O

Libro pagina 125:

4.53-  # gramos= M     V     Pm
            #gramos= (2.80)     (0.500 lt)     (87)
           #gramos= 121.8 gramos es la masa de IK.

4.55-  MaCl2 =  Cloruro de magnesio
                                      60.0 ml
                                      0.100 M
Ma= 24
Cl= 35*2=70
                 94 Pm                 
            Molaridad= # moles/ 1 lt sal
0.100 M= # moles/ 0.6 lt
0.100/ # moles= 0.6 H
Moles= 0.6/ 0.100 M=  # moles= 6
4.56:   Ko lt
            35.0 ml
            5.50 M
K= 39
O= 16              =56 Pm                            # gramos= 5.50 M     0.035 ml  * 56
H= 1                                                          #gramos= 107.8      
                                                                        107.8= 10.78 gr

4.59-  V= ?                                      Na= 23
                                                        Cl= 35                       =58
a) 2.14- NaCl
    0.270 M
                           # gramos= M  *V  *PM
                           #gramos= 0.270 *V * 58
                           2.14 g= 0.270 * V * 58  
                          2.14/58= 0.270 * V
                       2.14/0.270= 136.6 H
b)  4.30 g de estanol                       V=?
          1.50 M                            Estanol= C2 H S O H
C= 12*2= 24
H= 1*6= 6
O= 16= 16
              46 Pm                            430 g/ 1.50* 46= V
 0.0623 ml= V
623 lt= V

c) 0.85 g – acido acético= CH3 COO H
C= 12*2= 24
H= 1*4= 4                     = 60
O= 16*2= 32
0.85g/ 0.30*60= V
0.0472 ml= V
472 lt= V

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