We are going to use this equation:
ΔT = - i m Kf
when m is the molality of a solution
i = 2
and ΔT is the change in melting point = T2- 0 °C
and Kf is cryoscopic constant = 1.86C/m
now we need to calculate the molality so we have to get the moles of NaCl first:
moles of NaCl = mass / molar mass
= 3.5 g / 58.44
= 0.0599 moles
when the density of water = 1 g / mL and the volume =230 L
∴ the mass of water = 1 g * 230 mL = 230 g = 0.23Kg
now we can get the molality = moles NaCl / Kg water
=0.0599moles/0.23Kg
= 0.26 m
∴T2-0 = - 2 * 0.26 *1.86
∴T2 = -0.967 °C
Answer:
Density: Physical Property
Flammability: Chemical Property
Solubility In Water: Physical Property
Reactivity With Water: Chemical Property
Melting Pot: Physical Property
Color: Physical Property
Odor: Physical Property
Explanation:
:)
Answer: C. 25.6 kPa
Explanation:
The Gauge pressure is defined as the amount of pressure in a fluid that exceeds the amount of pressure in the atmosphere.
As such, the formula will be,
PG = PT – PA
Where,
PG is Gauge Pressure
PT is Absolute Pressure
PA is Atmospheric Pressure
Inputted in the formula,
PG = 125.4 - 99.8
PG = 25.6 kPa
The gauge pressure inside the container is 25.6kPa which is option C.
Answer: Option (A) is the correct answer.
Explanation:
Newton's third law states that when one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.
In short we can say that every action has an equal and opposite reaction.
For example, when we hit a wooden table hardly with our hands then we are applying a force on the table and on the other hand table is applying a force in the opposite direction on our hand due to which we get hurt.
Therefore, when force of gravity pulls the man in downward direction then man pulling upward on the earth is applying a force in opposite direction of gravitational pull.
Answer:
-1815.4 kJ/mol
Explanation:
Starting with standard enthalpies of formation you can calculate the standard enthalpy for the reaction doing this simple calculation:
∑ n *ΔH formation (products) - ∑ n *ΔH formation (reagents)
This is possible because enthalpy is state function meaning it only deppends on the initial and final state of the system (That's why is also possible to "mix" reactions with Hess Law to determine the enthalpy of a new reaction). Also the enthalpy of formation is the heat required to form the compound from pure elements, then products are just atoms of reagents organized in a different form.
In this case:
ΔH rxn = [(2 * -1675.7) - (3 * -520.0)] kJ/mol = -1815.4 kJ/mol