Answer:
Explanation:
1. Calculate the moles of CoF₂ needed
2. Calculate the mass of CoF₂
Molar mass Argon = <span>39.948 g/mol
number of moles = mass solute / molar mass
n = 150 / </span><span>39.948
n = 3.7548 moles
hope this helps!</span>
Answer:
Since I already answered the first two I will tell you the third one!
In general, the radiation heat transfer from one surface to another is the radiation leaving the first surface for the other minus that arriving from the second surface. Radiation heat transfer is mediated by electromagnetic radiation, known as thermal radiation, that arises due to the temperature of a body.
❤
To get the melting point of a solution so, we will use this formula:
ΔT = - mKf
when:
m is molality of the solution
Kf is cryoscopic constant of water = 1.86 C/m
and ΔT is the change in melting point (T2 - 0 °C)
so, now we need to calculate the molality to substitute:
when the molality = moles NaCl / Kg of water
and when moles NaCl = mass / molar mass
= 2.5 g / 58 g/mol
= 0.043 mol
∴ Kg water = volume *density /1000
= 230 mL * 1 g/mL / 1000
= 0.23 Kg
∴ molality = 0.043 / 0.23 =0.187 M
by substitution:
T2-0°C = - 0.187 * 1.86
∴T2 = - 0.348 °C
