por favor ayuda con este taller!!!!
Respuestas
Respuesta:
1. % m/m = 26.14 % g/g
2. 14.09 % p/p.
3. 3.49 Molar.
Explicación:
1. a. Calcular masa de la disolución utilizando la fórmula de densidad ( d = m/v)
m = d x v
m = 1.131 g/mL x 50 mL
m = 56.55 g
b. Calcular gramos de soluto ( % m/m = (m soluto/m solc.) x 100
m soluto = (12 g/g x 56.55 g ) / 100
m soluto = 6.786 g + 8 g = 14.786 g
c. Calcular masa de disolución total
masa = 56.55 g de disolución
d.% m/m = (14.786 g / 56.55 g) x 100
% m/m = 26.14 % g/g
2. a. Calcular masa de solución
m solc. = m soluto + m solvente
m solc. = 164 g + 1000 g = 1164 g
b. % m/m = (164 g / 1164 g) x 100
% m/m = 14.089 % g/g
3. Mm NH3 = 17 g/mol
solución 1: solución 2:
V= 25 mL V = 25 mL
4.9%p/p % 7.3
d = 0.979 g/mL d = 0.970 g/mL
1. calcula masa de cada solucion
d = m/v
masa solc.1
m = 0.979 g/mL x 25 mL
m = 24.475 g
masa solc. 2
m = 0.970 g/mL x 25 mL
m = 24.25 g
2. calcular masa soluto de cada solución
%p/p = masa soluto x 100
masa solución
masa soluto 1 = 4.9 g/g x 24.475 g
100
m soluto 1 = 1.1992 g
m soluto 2 = 7.3 g/g x 24.25 g
100
m soluto 2 = 1.7703 g
3. calcular M1 y M2
V = 25 / 1000 = 0.025 L
M1 = __ m___
Mm x V
M1 = __ 1.1992 g_____
17 g/mol x 0.025 L
M1 = 2.82
M2 = __1.7703 g__
17 g/mol x 0.025 L
M2 = 4.16
Concentración resultante: Cr
Cr = (M1 x V1) + (M2 x V2)
Vf
Cr = (2.82 M x 0.025 L) + (4.16 M x 0.025 L)
(0.025 + 0.025) L
Cr = (0.0705 M + 0.104 M) / 0.05
Cr = 3.49 M
4. Mm Na2CO3 = 106 g/mol
Convertir mg a g
g = 10.6 / 1000 = 0.0106 g
1. calcular mol = masa/Mm
mol = 0.0106 g / 106 g/mol
mol = 0.0001
v = 1 / 1000 = 0.001 L
M = mol/V(L)
M = 0.0001 mol / 0.001 L
M = 0.1
5. Mm Cafeína = 212 g/mol
M = mol soluto / V(L)
convertir mg a g
g = 125 / 1000 = 0.125 g
calcular mol
mol = masa/Mm
mol = 0.125 g/ 212 g/mol
mol = 0.0005896
M = 0.00058 mol / 0.125 L
M = 0.00471
6. a) M = 1.35 mol / 2.45 L
M = 0.55
b) Mm NaHCO3 = 84 g/mol
mol = 4.80 x 10⁻² g / 84 g/mol
mol = 0.005714
M = 0.0005714 g / 0.025 L
M = 0.022
c) M = 0.422 mol / 0.742 L
M = 0.569
7. % p/ v = (peso soluto/v solc.) x 100
Mm MgCl2 = 95.21 g/mol
1. solución = 100 / 1000 = 0.1 L
2. calcular nº de moles
n = m/Mm
n = 29 g/ 95.21 g/mol
n = 0.305 moles
3. calcular M = n/V(L)
M = 0.305 mol/0.100 L
M = 3.05 molar
8. Mm H2SO4 = 98 g/mol
D = m/v
m = d x v
m = 1.338 g/ml x 1000 ml
m = 1338 g solc
6.00 M = 6.00 moles / 1 litro
1 mol 98 g H2SO4
6 mol x g x = 588 g H2SO4
%masa = (m soluto / m solc.) x 100 %
masa = (588g / 1338g) x 100 =
% m/m = 43,9 % g/g
9. a. M = (% x d x 10) / Mm
Mm HCl = 36.5 g/mol
M = (35 g/g x 1.16 g/mL x 10) / 36.5 g/mol
M = 11.12 molar
b. 41.3 % p/p.
10. Mm (CH3CH2OH) = 46 g/mol
a. Calcular m de disolución ( d = m/v)
V = 1 L = 1000 mL
masa = 0.79 g/mL x 1000 mL
masa = 790 g de disolución
b. Calcular gramos de soluto
n = m/Mm
masa soluto = 17.1 mol x 46 g/mol
masa soluto = 786.6 g
c. Calcular % p/p
% p/p = (786.6 g / 760 g) x 100
% p/ p = 99.57 % g/g
11. Mm HCl = 36.45 g/mol
a. Calcular volumen en litros
V = 500 / 1000 = 0.500 L
b. Calcular moles de soluto despejando de la fórmula de Molaridad
M = n /V(L)
n = 4 mol/L x 0.500 L
n = 2 moles
c. Calcular gramos de HCl
n = masa/Mm
masa = 2 moles x 36.45 g/mol
masa = 72.9 g de HCl
12. Mm H3PO4 = 98 g/mol
a. Calcular moles de soluto
n = masa/Mm
n = 5 g / 98 g/mol
n = 0.051 moles de soluto
b. Calcular volumen en litros
V = 25 / 1000 = 0.025 L
c. Calcular molaridad
M = 0.051 mol / 0.025 L
M = 2.04 molar
13. Mm NaCl = 58.45 g/mol
d = 1.10 g/cm³
15 % m/m
M = 0.9 mol/L
1. Calcular masa de solución utilizando la fórmula de densidad
d = m/v
1 cm³ = 1 mL
m = 1.10 g / mL x 100 ml
m solución = 110 g
2. calcular masa soluto
%m/m = (m soluto / m solc.) x 100
m soluto = (15 g/g x 110 g) / 100
m soluto = 16.5 g
3. calcular los moles n = masa/Mm
n NaCl = 16.5 g / 58.45 g/mol
n NaCl = 0.282 mol
4. calcular volumen despejando de la fórmula de Molaridad
M = n / V(L)
V(L) = 0.282 mol / 0.9 mol/L
V(L) = 0.31333
5. Convertir L a mL
mL = 0.31333 x 1000
mL = 313.33
14. Mm ácido acético = 60 g/mol
a. Calcular masa de disolución
masa disolc. = 1.005 g/mL x 1000 mL
masa disolc. = 1005 g
b. Aplicar la fórmula:
m disolc. x __m s__ = __m s__
V disolc. m disolc. V disolc
1005 g x __5 g__ = 50.25 g/L
1 L 100 g
c. Calcular la molaridad
M = masa soluto
Mm x d
M = 50.25 g / (60 g/mol x 1 L)
M = 0.8375 molar
15. a) % p/p
1. calcular masa solc.
m solc. = 5 g + 35 g = 40 g 2.- Calcular % p/p
% p/p = ( 5 g / 40 g) x 100
% p/p= 12.5 % g/g
b) Molaridad
Mm HCl 0 36.5 g/mol
a. Calcular moles de soluto ( n = masa/Mm)
n = 5 g / 36.5 g/mol
n = 0.137 moles de soluto
b. Calcular volumen de la disolución
D = m/v
V = 40 g / 1.06 g/mL
V = 37.7 mL
c. Calcular volumen en litros
V = 37.74 / 1000
V = 0.0377 L
d. Calcular Molaridad
M = 0.137 moles / 0.0377 L
M = 3.634 molar
16. a) Molaridad
Mm Al2 (SO4)3 = 342.15 g/mol
a. calcular moles de soluto
n = 30 g / 342.15 g/mol
n = 0.0876 moles
b. calcular M
M = 0.0876 moles / 1.43 L
M = 0.061 molar
b) % p/p
1. calcular masa de disolución
masa = 1.43 g/mL x 1430 mL
masa = 2045 g de disolución
2. calcular % p/p
% p/p = (30g / 2045 g) x 100
% p/p = 1.467 % g/g
c) % p/v
% p/v = (p soluto / v solc.) x 100
% p/v = (30 g / 1430 mL) x 100
% p/v = 2.098 % g/mL