Answer:
16% v/v es la nueva concentración de alcohol en la solución
Explanation:
El porcentaje volumen/volumen (% v/v) es definido como 100 veces la relación entre el volumen de soluto (Alcohol en este caso) y el volumen total de la solución (Agua + Alcohol). Para resolver esta pregunta necesitamos hallar el volumen de alcohol y el de agua:
<em>Volumen alcohol:</em>
320cc * (20cc etanol / 100cc) = 64cc etanol
<em>Volumen agua:</em>
80cc + (320cc-64cc) = 336cc agua
<em>% v/v:</em>
64cc / (336cc + 64cc) * 100
= 16% v/v es la nueva concentración de alcohol en la solución
they are both types of passive transport which means they require no energy. They both work with the concentration gradient which means they go from a high concentration area to a low concentration area. The differences are simple diffusion just goes though the membrane of a cell while facilitated diffusion uses a protein channel
Simple diffusion: it is the process where molecules move from a area of high concentration to an are of lower concentration. There is no energy needed in simple diffusion. For example when sodium is highly concentration in a cell, it moves outside of the cell where sodium is less concentration. it takes no energy as simple diffusion is random and molecules move according to their concentration.
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-20.16 KJ of heat are released by the reaction of 25.0 g of Na2O2.
Explanation:
Given:
mass of Na2O2 = 25 grams
atomic mass of Na2O2 = 78 gram/mole
number of mole = 
= 
=0. 32 moles
The balanced equation for the reaction:
2 Na2O2(s) + 2 H2O(l) → 4 NaOH(aq) + O2(g) ∆Hο = −126 kJ
It can be seen that 126 KJ of energy is released when 2 moles of Na2O2 undergoes reaction.
similarly 0.3 moles of Na2O2 on reaction would give:
= 
x = 
= -20.16 KJ
Thus, - 20.16 KJ of energy will be released.
Answer:
After the solution is heated, but before additional solute is added
Explanation:
An unsaturated solution is a solution that contains less solute than it can normally hold at a given temperature. Hence an unsaturated solution can still dissolve more solute.
When the solution is heated, the saturated cold solution becomes an unsaturated hot solution which is capable of dissolving more solute at this point.
Once more solute is dissolved, the solution becomes saturated again just before it begins to cool since no more solute dissolves in the solution at some point before cooling and addition of seed crystals.
