Answer:
Molality = 8.57 m
Explanation:
Given data:
Molarity of solution = 5.73 M
density = 0.9327 g/mL
Molality of solution = ?
Solution:
Molality = moles of solute / kg of solvent.
Kg of solvent:
Mass of 1 L solution = density× volume
Mass of 1 L solution = 0.9327 g/mL × 1000 mL
Mass of 1 L solution = 932.7 g
Mass of solute:
Mass of 1 L = number of moles × molar mass
Mass = 5.73 mol × 46.068 g/mol
Mass = 263.97 g
Mass of solvent:
Mass of solvent = mass of solution - mass of solute
Mass of solvent = 932.7 g - 263.97 g
Mass of solvent = 668.73 g
In Kg = 668.73 /1000 = 0.6687 Kg
Molality:
Molality = number of moles of solute / mass of solvent in Kg
Molality = 5.73 mol / 0.6687 Kg
Molality = 8.57 m
Explanation:
As per the Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
Hence, according to this law the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
..........(1)
..............(2)
The final reaction is as follows:
.............(3)
Therefore, adding (1) and (2) we get the final equation (3) and value of
at 298 K will be as follows.
=
+
= -314 kJ + (-80) kJ
= -394 kJ
Thus, we can conclude that
at 298 K for the given process is -394 kJ.
Answer:
the average mass of the atoms of an element measured in an atomic mass unit
Explanation:
Answer:
The postulate of Dalton's atomic theory that an atom is an indivisible particle and cannot be subdivided into smaller particles was later changed because atoms can be divided into neutrons, protons and electrons.
Explanation:
Answer:
The most appropriate unit to use for a redwood is:
Explanation:
The largest tree in the world is called Hyperion and it is a <em>Sequoia sempervirens</em>, that is to say, a redwood, which measures a little more than 115 meters, when knowing this data first hand, you can imagine that <u>the vast majority of trees are usually measured in meters since their size is usually one meter in ahead (although you should know that there are some shrub species that can measure only centimeters, but being a minority, the meter unit is usually used)</u>.