Ask for help with PH problems in the second year of high school. The relationship between PH and POH

The answers are HCL CH3COOH

The difference between pH and concentration is that for hydrochloric acid, since hydrochloric acid is a strong acid and completely ionized, hydrochloric acid with pH=1 is hydrochloric acid with a concentration. However, for acetic acid, since acetic acid is a weak acid, it can only be ionized in a small part, so if the pH of acetic acid is equal to 1, then its concentration is much greater.

In other words, if it is acetic acid, then it is less acidic, with a pH greater than 1.

First, the same pH dilution, acetic acid is highly acidic, and the pH is smaller. This is because, hydrochloric acid is a strong acid and has been completely ionized, while acetic acid is a weak acid, and if it is diluted with water, the ionization balance shifts to the right, and a part of it will be ionized. Originally, the pH of the two was equal, but the acetic acid was further ionized after dilution, so the acidity of acetic acid became stronger than that of diluted hydrochloric acid.

The pH of acetic acid is small, and the pH of hydrochloric acid is large.

Second, for both, that is, the concentration is equal and small, all diluted 100 times, and the concentration has become, but hydrochloric acid is completely ionized, and acetic acid is not completely ionized, so hydrochloric acid is acidic, pH is small, and acetic acid pH is large.

The fundamental difference between these two questions is that the concentration of hydrochloric acid and acetic acid with equal pH is unequal, and the concentration of acetic acid is much larger.

Pure original hand-played, detailed explanation ignores all the answers above.

The first is that the hydrochloric acid with large acetic acid and pH = 1 is completely ionized with a concentration of , while the acetic acid is not completely ionized with a concentration greater than that, and the diluted hydrochloric acid is , pH = 3, while acetic acid is greater than 3;

The second concentration is the same, the diluted concentration is still the same, acetic acid is not completely ionized, acetic acid is not completely ionized, so the pH of hydrochloric acid = 3, and the pH of acetic acid is greater than 3;

The pH of hydrochloric acid = 1, while the acetic acid is not completely ionized, and the pH is greater than 1; The concentration of hydrochloric acid with ph=1 is, and the concentration of acetic acid with ph=1 is greater than;

I hope you understand that it's a strong acid that is completely ionized; Weak acids are not completely ionized;

HCl) acetic acid is a weak electrolyte, which will continue to ionize after adding water, and its pH is smaller than that of hydrochloric acid.

CH3Cooh) is a weak electrolyte, with a small degree of ionization, a small H ion concentration, and a large pH.

is the amount concentration of the substance, and the pH is related to the concentration of the H ion obtained by ionization, and the pH = 1 hydrochloric acid.

The amount concentration of the substance is less than that of acetic acid.

The first one is hydrochloric acid, and the second is acetic acid.

At room temperature, the HCl of mol L is also the HCl of pH=1, because hydrochloric acid is a strong electrolyte, it is completely ionized in the aqueous solution, and the concentration of hydrogen ions is also mol L, according to the method of pH, it can be obtained as 1But since acetic acid is a weak electrolyte, it is not completely ionized in aqueous solution, and the concentration of hydrogen ions is less than mol l, which can be obtained according to the method of pH greater than 1

If the pH is the same, because acetic acid is a weak acid, the concentration must be greater than that of hydrochloric acid, and the addition of water will also promote ionization, so the pH of hydrochloric acid after dilution is larger.

And if the concentration is the same, acetic acid only ionizes a small part, so the pH is much higher than hydrochloric acid at the beginning, and even if it is ionized after adding water, it will not have a great effect, so in the end, the pH of acetic acid is larger.

HCI acetic acid is a weak electrolyte that cannot be completely ionized in solution, so the concentration of hydrogen ions is less than that of hydrochloric acid, so the pH of hydrochloric acid is large.

HCL Ibid.

It doesn't make much difference because pH = -LG (concentration of hydrogen ions) supplementation: when the solution of C(H+) or C(OH-) is greater than 1mol L, it is very inconvenient to use pH.

For example, if C(H+)1mol L, its pH is 0

And when C(H+)2mol L, the pH is.

So at this time. Indicates the acidity and alkalinity of the solution, directly expressed by H+ or Oh+ concentration!

1) The pH of hydrochloric acid is large, because hydrochloric acid is a strong acid, and after dilution 100 times, the pH is 3; Acetic acid is a weak acid, and after dilution, it is also hydrolyzed, so the pH < 3

2) Acetic acid. 3) The pH of the first one is not equal to 1

Sulfuric acid is a strong acid that is completely ionized, and acetic acid is a weak acid that is not completely ionized, and this is the difference.

The first one is hydrochloric acid, and the second is acetic acid.

In water, the concentration of hydrogen ions and hydroxide ions at the same temperature.

The product of concentration is the amount of concentration of a substance with a certain pH=-lg[H+](H+) concentration of hydrogen ions in water.

Unit: mol l) In the same way, at 20 degrees PoH=-Lg[OH-]=10 -14, so this Changyan time Nai's Royal pH+PoH=14 This result varies with temperature.

1. Solution: C(H+)=10 -2mol L in hydrochloric acid solution when pH=2

When pH = 4, c(H+) = 10 -4mol L in hydrochloric acid solution

After mixing, the hydrochloric acid solution obtained c(h+)=(10-2mol l*v+10-4mol l*v) (v+v)=10-2mol l2

Note: 10-4mol L is more different from 10-2mol L, and 10-4mol L is negligible).

ph=-lg（10^-2mol/l/2）=-(1g10^-2mol/l-1g2)=-(

Answer: The pH of the resulting solution is.

2. When pH = 11, C (H+) = 10 -11mol L in Ba(OH)2 solution

c(oh^-)=10^-14/10^-11=10^-3mol/l

When pH = 9, C(H+) = 10 -9mol L in Ba(OH)2 solution

c(oh^-)=10^-14/10^-9=10^-5mol/l

In the mixed Ba(Oh)2 solution, C(OH -) = (10 -3mol L*V + 10 -5mol L*V) (V+V) = 10 -3mol L2

Note: 10-5mol L is more different from 10-3mol L, and 10-5mol L is ignored).

c(h^+)=10^-14/[10^-3mol/l/2]=2*10^-11mol/l

ph=-lg（2*10^-11mol/l）=-(1g2+lg10^-2mol/l)=-(

Answer: The pH of the resulting solution is.

3. Solution: After mixing hydrochloric acid and sodium hydroxide solution in equal volumes, the amount of remaining hydrogen and oxygen in the solution according to the amount of ionic substances is:

n = c (oh -) = in the mixed solution

c(h^+)=10^-14/10^-mol/l=10^-13mol/l

ph=-1g(10^-13mol/l)=13

Answer: The pH value of the resulting solution = 13

Here's my personal opinion.

Combining two equations: Cr3++4OH "= Reversible=" CRO2 +2H2O, CR2(SO4)3 solution 50ml contains Cr3+ That is, 50ml of NaOH solution contains OH-, generating CRO2, consumes OH- i.e., the remaining OH- That is, the volume of the mixed solution is approximately unchanged, about 50ml+50ml=, that is, the concentration of hydroxide in the solution after sufficient reaction is that is, the imitation L, and when the concentration of OH- is greater than that of the regretful brother, the solution HP is greater than 13, so, Judging from the meaning of the title, the phenomenon detected by the observable blue bump in the solution in this question should be that the solution c is bright green.

So choose C

pH is the commonly log-negative value of the concentration of hydrogen ions, i.e., pH=-LG[H+].h+].

For the hydrogen ion concentration, PoH is also a common log-negative value for the OH- ion concentration, i.e., POH=-LG[OH-].oh-].

It is water-soluble with a hydrogen ion concentration of 25 degrees Celsius.

In the container, the relationship between POH and pH value:

ph+poh=

So, ph =

In calculating the pH of an alkaline solution, the POH of the solution must be calculated first, and then the pH of the solution must be calculated from pH =

3 or 11

The H+ concentration of water ionization is 10-11 mol L. The former pH = 3 and the latter pH = 11

For the former, the concentration of H+ ionized by HCl is, then the concentration of OH- is 10 -11 mol L, and these OH- are ionized by water, and every time water ionizes an OH-, it must ionize an H+ at the same time, so the concentration of H+ ionized by water is 10 -11 mol L

For the latter, the concentration of OH- ionized by NaOH is 10 -11 mol L, and these H+ are ionized by water.

pH = - log10 molar concentration of hydrogen ions in the solution, so the pH of this solution is 11 Gr.

When calculating the pH of a solution, it is important to grasp the acidity and alkalinity of the solution, especially the mixed solution

If the mixed solution is neutral, the column formula makes the hydrogen ion concentration equal to the hydroxide concentration;

If the solution is acidic after mixing, the hydrogen ion concentration of the solution is directly converted to pH by the formula If the solution is alkaline after mixing, it is necessary to pay attention to calculate the concentration of hydroxide ions in the solution first, and then convert the concentration of hydrogen ions according to the value of kw (pay attention to whether it is normal), and then calculate the pH of the solution.

Let the volume of strong alkali be A, the volume of strong acid is B, the neutralization reaction occurs when mixing, and finally pH is equal to 11, indicating that the alkali is excessive and the remaining alkali is left.

pH==13, then the hydroxide concentration is equal to; pH==2, then the hydrogen ion concentration is equal to; pH is equal to 11 i.e. hydroxide concentration is equal to.

A:b==9:1 is obtained