Exprese la concentración de una solución de H3PO4 al 30 % en masa y con una densidad de 1.39 g/mL en: M, y N.

Respuesta:

4.26 M; 12.8 N

Explicación:

Primer paso: Calcular la concentración volumétrica (Cv)

Usaremos la siguiente expression.

Cv = Cg × ρ

Cv = 30 g%g × 1.39 g/mL = 41.7 g%mL

Segundo paso: Calcular la molaridad

La concentración volumetrica es 41.7 g%mL, es decir, hay 41.7 gramos de soluto cada 100 mL de solución. Usaremos la siguiente fórmula para molaridad.

M = masa de soluto / masa molar de soluto × litros de solución

M = 41.7 g / 97.99 g/mol × 0.1 L = 4.26 M

Tercer paso: Calcular la normalidad

Usaremos la siguiente fórmula.

N = M × Z

donde Z para un ácido es igual al número de protones.

N = M × Z

N = 4.26 mol/L × 3 eq/mol = 12.8 N

all eukaryotic cell have mitochondria : )

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2