We are given that the balanced chemical reaction is:
cacl2⋅2h2o(aq) +
k2c2o4⋅h2o(aq) --->
cac2o4⋅h2o(s) +
2kcl(aq) + 2h2o(l)
We known that
the product was oven dried, therefore the mass of 0.333 g pertains only to that
of the substance cac2o4⋅h2o(s). So what we will do first is to convert this
into moles by dividing the mass with the molar mass. The molar mass of cac2o4⋅h2o(s) is
molar mass of cac2o4 plus the
molar mass of h2o.
molar mass cac2o4⋅h2o(s) = 128.10
+ 18 = 146.10 g /mole
moles cac2o4⋅h2o(s) =
0.333 / 146.10 = 2.28 x 10^-3 moles
Looking at
the balanced chemical reaction, the ratio of cac2o4⋅h2o(s) and k2c2o4⋅h2o(aq) is
1:1, therefore:
moles k2c2o4⋅h2o(aq) = 2.28
x 10^-3 moles
Converting
this to mass:
mass k2c2o4⋅h2o(aq) = 2.28
x 10^-3 moles (184.24 g /mol) = 0.419931006 g
Therefore:
The mass of k2c2o4⋅<span>h2o(aq) in
the salt mixture is about 0.420 g</span>
Answer:
Explanation:
Equation of the reaction:
NaOH + HCl --> NaCl + H2O
Volume of HCl = 5 ml
Molar concentration = 1 M
Number of moles = molar concentration * volume
= 1 * 0.005
= 0.005 mol of HCl
By stoichiometry, 1 mole of HCl completely neutralizes 1 mole of NaOH
Therefore, number of moles of NaOH = 0.005 mol
Molar mass of NaOH = 23 + 16 + 1
= 40 g/mol
NaOH --> Na+ + OH-
Mass = molar mass * number of moles
= 40 * 0.005
= 0.2 g of Na+
Answer:
HCl, ya que la sustancia es una base que se debe titular con un ácido.
Explanation:
¡Hola!
En este caso, teniendo en cuenta la descripción inicial de la sustancia, la cual se torna violeta cuando se le agrega la fenolftaleína, es posible inderir que esta sustancia es una base con pH básico. Ahora bien, en torno a la especificación de un proceso de titulación, es claro que dicha base debe ser titulada con un ácido, y este caso, con HCl, ácido chlorhídrico, con el fin the alcanzar el punto de equivalencia.
¡Saludos!
D) warm and wet.
Water can be a catalyst, and heat speeds up reactions.
Answer:
False
Explanation:
Temperature is also heat energy, so chemical energy has no affect over it.
