Answer:
666.93 kJ
Explanation:
Using the formula;
Q = m × c × ∆T
Where;
Q = amount of heat absorbed (Joules)
m = mass of substance (g)
c = specific heat capacity (4.184 J/g°C)
∆T = change in temperature (°C)
Based on the information provided in the question;
Q = ?
m = 2000g
∆T = 99.7 °C - 20 °C = 79.7 °C
c = 4.184 J/g°C
Using Q = m × c × ∆T
Q = 2000 × 4.184 × 79.7
Q = 666929.6 Joules
To calculate the amount of heat absorbed (Q) in kilojoules (kJ), we say;
1 joule = 0.001 kilojoule
666929.6 Joules = 666929.6 × 0.001
= 666.9296 KJ
Approximately, Q = 666.93 kJ.
Answer:
737.52 mL de agua
Explanation:
En este caso solo debes usar la expresión de molaridad de una solución la cual es:
M = moles / V
Donde:
V: Volumen de solución.
Como queremos saber la cantidad de agua, queremos saber en otras palabras cual es la cantidad de solvente que se utilizó para preparar los 800 mL de disolución.
Una disolución se prepara con un soluto y solvente. El soluto lo tenemos, que es el nitrato de plata. Con la expresión de arriba, calculamos los moles de soluto, y luego su masa. Posteriormente, calculamos el volumen con la densidad, y finalmente podremos calcular el solvente de esta forma:
V ste = Vsol - Vsto
Primero calcularemos los moles de soluto:
moles = M * V
moles = 2 * 0.800 = 1.6 moles
Con estos moles, se calcula la masa usando el peso molecular reportado que es 169.87 g/mol:
m = moles * PM
m = 1.6 * 169.87 = 271.792 g
Ahora usando el valor de la densidad, calcularemos el volumen de soluto empleado:
d = m/V
V = m/d
V = 271.792 / 4.35
V = 62.48 mL
Finalmente, la cantidad de agua necesaria es:
V agua = 800 - 62.48
V agua = 737.52 mL
The only thing I remember from high school biology is that the mitochondria is the powerhouse of the cell. They are the energy factory of the cell, meaning that they 3) release energy from nutrients.
The dichloromethane (DCM) has less density than water and also the polarity of water is much more than DCM. So the mixture of water and dichloromethane will always be a heterogeneous mixture. In the mixture dichloromethane will be always up of the water layer. The volume of the separatory funnel which contains the mixture of DCM and water must have to be more than the total volume of the liquids thus the volume of the funnel will be more than (50+50) = 100mL.
The caution have to consider during the separation are-
1. The separatory funnel have to shake well with lid and have to settle down for some times until the two liquid separated.
2. The lid should be open very slowly as the vapor pressure of DCM is more and it will float on the water.
3. After this the stopcock should be opened and slowly the water will come out first followed by DCM.
Homogeneous mixtures.
Hope this helps.
