Answer:
The answer to your question is: letter D.
Explanation:
Noble gases are located in group VIIIA of the periodic table, this means that they have 8 eight electrons in their outermost shell.
Due to this characteristic, they are stable and do not react with other elements.
a. 1s22s22p4 The outermost shell of this electron configuration has 6 electrons, then this element has 6 electrons not 8. This configuration is of an element of the group VIA.
b. [Ne]2s22p2 The outermost shell of this element has 4 electrons, so this is not the configuration of a noble gas.
c. [Ar] 3s1 This element only has one electron in its outermost shell, so this is the electron configuration of an alkaline metal.
d. 1s22s22p6 This element has 8 electrons in its outermost shell, so this is the electron configuration of a noble gas.
Answer:

Explanation:
Molarity is a measure of concentration in moles per liter.

The molarity of the solution is 1.2 M NaNO₃ or 1.2 moles NaNO₃ per liter. There are 0.25 liters of the solution. The moles of solute are unknown, so we can use x.
- molarity= 1.2 mol NaNO₃/L
- liters of solution=0.25 L
- moles of solute =x

We are solving for x, so we must isolate the variable, x. It is being divided by 0.25 liters. The inverse of division is multiplication, so we multiply both sides by 0.25 L.


The units of liters cancel, so we are left with the units moles of sodium nitrate.


There are 0.3 moles of sodium nitrate.
Answer:
Explanation:
To solve the problem, we must know the kind of compounds we are dealing with.
For the first compound, P1 and second compound P2:
N O N O
Mass percent 64.17 35.73 47.23 52.79
Atomic mass 14 16 14 16
Number of
moles 64.17/14 35.73/16 47.23/14 52.79/16
4.58 2.23 3.37 3.30
Simplest
ratio 4.58/2.23 2.23/2.23 3.37/3.30 3.3/3.3
2 1 1 1
P1 compound is N₂O
P2 compound is NO
These are the compounds,
In N₂O = 28:16
NO = 14:16
This is the ratio of nitrogen to a fixed mass of oxygen for the two compounds.
Answer:

Explanation:
Hello!
In this case, since the net ionic equations are ionic representations of the molecular equation in which the spectator ions (those at both reactants and products sides) are cancelled out, we first write the complete ionic equation for this reaction, considering that the solid silver chloride is not ionized due to its precipitation:

Whereas the nitrate and sodium ions are cancelled out for the aforementioned reason as they are the spectator ions, to obtain:

Which is the required net ionic equation.
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Answer: c. Matter and energy are conserved in chemical reactions.
Explanation:
According to the law of conservation of matter, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side.
For every chemical reaction, the law of conservation of energy is applicable which states that the energy of the system remains conserved. Energy can neither be created nor destroyed. It can be transformed from one form to another.