Question

Halla la concentración normal (N) de 200 ml de una solución acuosa 1,8 M de H2SO4

Answer 1

Mm H2SO4 = 98 g/mol

1.  convertir mL  a L

L = 200 / 1000 = 0.2 Litros

2. calcular moles despejando de la fórmula M =  n/V(L)

n = 1.8 mol/ L  x  0.2 L = 0.36 moles

3.. calcular masa  aplicando la fórmula  n = masa/Mm

masa = 0.36 mol x 98 g/mol

masa = 35.28 g

4. calcular Peq = Mm/ Nº H⁺

Peq. = 98 g/mol
           ````````````
                 2

Peq. = 49 g/eq

5. calcular equivalentes:

eqv. = masa/Peq.

eqv. = 35.28 g/ 49 g/eq

eq. = 0.72

6. calcular N = eq. / V(L)

N = 0.72 eq. / 0.2 L

N = 3.6 normal

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2da. forma directa.

M = N
       ``
       2

entonces: N = 2M

sustituir:  N = 2(1.8) = 3.6 Normal