The answer is (4) at the cathode, where reduction occurs. The Na+ gains one electron and become Na(l). So the reaction occurs at cathode and is reduction reaction.
Answer:
The percent by mass of 3.55 g NaCl dissolved in 88 g water is 3.88%
Explanation:
When a solute dissolves in a solvent, the mass of the resulting solution is a sum of the mass of the solute and the solvent.
A percentage is a way of expressing a quantity as a fraction of 100. In this case, the percentage by mass of a solution is the number of grams of solute per 100 grams of solution and can be represented mathematically as:

In this way it allows to precisely establish the concentration of solutions and express them in terms of percentages.
In this case:
- mass of solute: 3.55 g
- mass of solution: 3.55 g + 88 g= 91.55 g
Replacing:

Percent by mass= 3.88%
<u><em>The percent by mass of 3.55 g NaCl dissolved in 88 g water is 3.88%</em></u>
Answer:
Se detailed explanation.
Explanation:
Hello,
In this case, since both magnesium and calcium ions are in group IIA, we can review the following similar properties:
- Since both calcium and magnesium are in group IIA they have two valence electrons, it means that the both of them have two electrons at their outer shells.
- They are highly soluble in water when forming ionic bonds with nonmetals such as those belonging to halogens and oxygen's family.
- Calcium has 18 electrons and magnesium 10 which are two less than the total protons (20 and 12 respectively) since the both of them have lost two electrons due their ionized form.
- Their electron configurations are:

It means that the both of them are at the
region since it is the last subshell at which their electrons are.
Best regards.
Answer:
3
Explanation:
Atomic number refers to the number of protons in the nucleus of the atom.
and since there are 3 protons, the atomic number is 3
Answer:
[HOCH₂CH₂OH] = 24.1 m
Explanation:
Ethylene glycol → HOCH₂CH₂OH
60% by mass means that 60 g of ethylene glycol are contained in 100 g of solution.
Solution mass = Solute mass + Solvent mass
100 g = 60 g + Solvent mass
Solvent mass = 40 g
Molality are the moles of solute contained in 1kg of solvent.
We determine the moles of solute → 60 g . 1mol/62 g = 0.967 moles
We convert the mass of solvent from g to kg → 40 g . 1kg/1000 g = 0.04 kg
Molality → 0.967 mol / 0.04 kg = 24.1 m