Answer:
freezing point (°C) of the solution = - 3.34° C
Explanation:
From the given information:
The freezing point (°C) of a solution can be prepared by using the formula:

where;
i = vant Hoff factor
the vant Hoff factor is the totality of the number of ions in the solution
Since there are 1 calcium ion and 2 nitrate ions present in Ca(NO3)2, the vant Hoff factor = 3
= 1.86 °C/m
m = molality of the solution and it can be determined by using the formula

which can now be re-written as :



molality = 0.599 m
∴
The freezing point (°C) of a solution can be prepared by using the formula:



the freezing point of water - freezing point of the solution
3.34° C = 0° C - freezing point of the solution
freezing point (°C) of the solution = 0° C - 3.34° C
freezing point (°C) of the solution = - 3.34° C
Answer:
The Battery Casing
Battery casing is manufactured in layers. The casing layers are developed from various raw materials and can include one or two, for example, polyethylene terephthalate layers, a polymer layer, and a polypropylene layer.
Explanation:
pH=2.7
<h3>Further explanation</h3>
Acetic acid = weak acid
![\tt [H^+]=\sqrt{Ka.M}](https://tex.z-dn.net/?f=%5Ctt%20%5BH%5E%2B%5D%3D%5Csqrt%7BKa.M%7D)
Ka = acid ionization constant
M = molarity
Ka for Acetic acid(CH₃COOH) : 1.8 x 10⁻⁵
![\tt [H^+]=\sqrt{1.8\times 10^{-5}\times 0.222}\\\\=0.001998=1.998\times 10^{-3}](https://tex.z-dn.net/?f=%5Ctt%20%5BH%5E%2B%5D%3D%5Csqrt%7B1.8%5Ctimes%2010%5E%7B-5%7D%5Ctimes%200.222%7D%5C%5C%5C%5C%3D0.001998%3D1.998%5Ctimes%2010%5E%7B-3%7D)

Answer:
The correct row is B.
Explanation:
The formation of the magnesium ion, Mg²⁺, comes from the removal of 2 electrons from the valence shell of the magnesium atom.<em> </em>Since the remotion is of electrons, the nucleus of the atom remains the same, so the number of protons and the number of neutrons does not change.<em> </em>
If the number of proton change, then the atom also change, since the identity of an atom is related to the atomic number which is the same to the proton number.
Now, if the number of neutrons changes, then we would be in the presence of an isotope of the magnesium atom.
Therefore, the correct row is B.
I hope it helps you!