Answer:
28%
Explanation:
Primero <u>calculamos los mililitros de etanol presentes en la primera solución</u>:
- 200 mL * 70/100 = 140 mL etanol
Para calcular el nuevo porcentaje en volumen, dividimos los mililitros de etanol (<em>que permanecen iguales durante el proceso de dilución</em>) entre el volumen final.
- Volumen final = 200 mL + 300 mL = 500 mL
- % Volumen de Etanol = 140 mL / 500 mL * 100% = 28%
The molarity of Sr(OH)2 solution is = 0.1159 M
calculation
write the equation for reaction
that is, Sr(OH)2 +2HCl→ SrCl2 + 2 H2O
then finds the mole of HCl used
moles = molarity x volume
=40.03 x0.1159 = 4.639 moles
by use of mole ratio between Sr(OH)2 to HCL which is 1 :2 the moles of Sr(OH)2 is therefore = 4.639 x1/2 = 2.312 moles
molarity of Sr(OH)2 is = moles / volume
=2.312 /20 =0.1159 M
The 2 L of sucrose stock solution would contain similar
concentration with the 100 mL aliquot. Therefore the concentration of aliquot
is still 2 M.
The molar mass of sucrose is 342.3 g / mol. Therefore the
mass in a 100 mL (0.1 L) aliquot is:
mass = (2 mol / L) * 0.1 L * (342.3 g / mol)
<span>mass = 68.46 g</span>
Answer:
W = 278.64375 Joules
Explanation:
The information given in this problem are;
Initial volume = 0L
Final volume = 2.50L
ΔV = 2.50 - 0 = 2.50 L
External pressure, P = 1.10 atm
Work = ?
These parameters are related by the equation;
w = - P ΔV
W = - (1.10 )(2.50)
W = 2.75 L atm
Upon conversion to joules;
1 liter atmosphere is equal to 101.325 joule
W = 278.64375 Joules