The third question requires you to solve for the weight of sodium (Na) and weight of Chloride (Cl) from the calculated moles of each element Na, and Cl.
So, you need to multiply the calculated moles of Na with its molar mass (23 g/ mol) to get the answer for Na. And multiply the calculated moles of Cl with its molar mass (35.45 g/mol) to get the answer for Cl.
Answer : Yes, a precipitate form when a solution of calcium chloride and a solution of mercury(I) nitrate are mixed together.
The net ionic equation will be,

Explanation :
In the net ionic equations, we are not include the spectator ions in the equations.
Spectator ions : The ions present on reactant and product side which do not participate in a reactions. The same ions present on both the sides.
The given balanced ionic equation will be,

The ionic equation in separated aqueous solution will be,

In this equation,
are the spectator ions.
By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.
The net ionic equation will be,

Answer:
Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. Hope it helps ;)
Answer: The correct answer is- Replication of DNA ( deoxyribonucleic acid) must happen before a body cell can begin mitotic cell division.
Mitotic division is a type of cell division in which a parent cell divides two identical daughter cells ( through a series of five stages that is- prophase, metaphase, anaphase, telophase, and cytokinesis) having same number of chromosomes as that of the parental cell.
It occupies the second stage of cell cycle, the first being interphase ( which has three stages that is G1, S, and G2 phase). Replication of DNA takes place in the interphase ( particulary in the S phase) so that cell is ready to divide in the mitotic phase.
Thus, replication of DNA ( deoxyribonucleic acid) must happen before a body cell can begin mitotic cell division.
Answer:
Y = 92.5 %
Explanation:
Hello there!
In this case, since the reaction between lead (II) nitrate and potassium bromide is:

Exhibits a 1:2 mole ratio of the former to the later, we can calculate the moles of lead (II) bromide product to figure out the limiting reactant:

Thus, the limiting reactant is the KBr as it yields the fewest moles of PbBr2 product. Afterwards, we calculate the mass of product by using its molar mass:

And the resulting percent yield:

Regards!