The charge of an e- is 1.60217657×10^-19 coulombs I.e. A very small number!
So 1 coulomb is much much bigger than the charge of an electron.
Answer:
Chloroform is expected to boil at 333 K (60
).
Explanation:
For liquid-vapor equilibrium at 1 atm,
= 0.
We know,
, where T is temperature in kelvin scale.
Here both
and
are corresponding to vaporization process therefore T represents boiling point of chloroform.
So, ![0=(31.4\times 10^{3}\frac{J}{mol})-[T\times (94.2\frac{J}{mol.K})]](https://tex.z-dn.net/?f=0%3D%2831.4%5Ctimes%2010%5E%7B3%7D%5Cfrac%7BJ%7D%7Bmol%7D%29-%5BT%5Ctimes%20%2894.2%5Cfrac%7BJ%7D%7Bmol.K%7D%29%5D)
or, T = 333 K
So, at 333 K (60
) , chloroform is expected to boil.
Answer:
The volume of stock solution needed to make the solution is 1875 ml
Explanation:
The parameters given are;
The volume of 75 M solution of H₂SO₄ = 400 ml
The concentration of stock solution = 16.0 M
Number moles per liter of stock solution = 16 moles
Number of moles in required 400 ml solution = 0.4×75 = 30 M
Volume of stock solution that contains 30 M = 30/16×1 = 1.875 l
The volume of stock solution that is required = 1875 ml
Answer:
Option a.
Explanation:
The transformation of a solid into liquid is a slow process, hence a rate of heating too fast, near the melting point of the sample, will not give the right time to the crystals of the sample to absorb the heat and to melt in the outside and the inside, leading to wrong results in all cases. If we heat to fast, the melting point range will be too broad and will be misleading, resulting in values of the range more hight than the theoric ones.
A rate of 1 °C/min or 2 °C/min is the most appropriate to approach the melting point of the sample. Since it is too slow, from preventing the experiment taking forever it is recommended to start the experiment at a high heating rate until it reaches 20 °C below the melting point, and then, turn the heating rate down to 1 °C/min or 2 °C/min.
Therefore, the correct answer is a: near the melting point of the sample, we must heat slowly until it reach the expected temperature.
I hope it helps you!