Answer:
0.00230 = <u>3 significant figures</u>
Explanation:
Significant digits or figures of a given number are the digits or figures that have meaning and contributes to the precision of the given number.
Therefore, <u>0.00230 = 3 significant figures.</u>
Reason: The non-zeros figures and the trailing zero after the decimal are significant. Whereas, all the leading zeros are not considered significant.
.54 km to dm is 5,400 decimeters. Hope this helps, have a BLESSED day! :-)
Answer: The concentrations of
at equilibrium is 0.023 M
Explanation:
Moles of
= 
Volume of solution = 1 L
Initial concentration of
= 
The given balanced equilibrium reaction is,

Initial conc. 0.14 M 0 M 0M
At eqm. conc. (0.14-x) M (x) M (x) M
The expression for equilibrium constant for this reaction will be,
![K_c=\frac{[CO]\times [Cl_2]}{[COCl_2]}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B%5BCO%5D%5Ctimes%20%5BCl_2%5D%7D%7B%5BCOCl_2%5D%7D)
Now put all the given values in this expression, we get :

By solving the term 'x', we get :
x = 0.023 M
Thus, the concentrations of
at equilibrium is 0.023 M
Answer: K only has 1 valence electron. It will leave with only a little effort, leaving behind a positively charged K^+1 atom.
Explanation: A neutral potassium atom has 19 total electrons. But only 1 of them is in potassium's valence shell. Valence shell means the outermost s and p orbitals. Potasium's electron configuration is 1s^2 2s^2 2p^6 3s^2 3p^6 4s^1. The 4s orbital is the only orbital in the 4th energy level. So it has a valency of 1. This means this electron will be the most likely to leave, since it is the lone electron in the oyutermost energy level (4). When that electron leaves, the charge on the atom go up by 1. The atom now has a full valence shell of 3s^2 3p^6, the same as argon, Ar.
<span>A solution with a pH of 4 has ten times the concentration of H</span>⁺<span> present compared to a solution with a pH of 5.
</span>pH <span>is a numeric scale for the acidity or basicity of an aqueous solution. It is the negative of the base 10 logarithm of the molar concentration of hydrogen ions.
</span>[H⁺] = 10∧-pH.
pH = 4 → [H⁺]₁ = 10⁻⁴ M = 0,0001 M.
pH = 5 → [H⁺]₂ = 10⁻⁵ M = 0,00001 M.
[H⁺]₁ / [H⁺]₂ = 0,0001 M / 0,00001 M.
[H⁺]₁ / [H⁺]₂ = 10.