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During electrolysis, the metal on the anode undergoes an oxidation reaction in the order of reduction from strong to weak (Zn>Fe>Ni> Cu> Pt), i.e., Zn Zn2+ +2E

fe→ fe2+ +2e－

ni→ ni2+ +2e－

In the electrolysis process, because crude nickel contains a small amount of impurities such as Fe, Zn, Cu, and Pt, when the anode dissolves Fe, Zn, Ni and the cathode precipitates Ni, the total number of electrons gained and lost is equal, and the mass of the anodic decreased cannot be equal to the mass increased by the cathode. After electrolysis, the metal cations present in the solution may also have Ni2+ in addition to Fe2+ and Zn2+; Because fe, znIt is more active than Ni, so it is impossible to have Fe and Zn in the anode mud at the bottom of the electrolytic cell, only Cu and Pt exist.

So the answer: is d

Option A: Analyze the change of the mass of the two poles The anode Zn Fe is dissolved, while the Ni precipitated by the cathode at this time, the dissolved and precipitated masses are not equal, so the change values of the mass of the two electrodes are unequal.

Option B: There should be Ni2+ in the initial electrolyte solution, Zn2+ and Fe2+ after electrolysis, but there is still Ni2+, so it is wrong.

Option C: CU and PT are not ni active, but precipitate directly at the bottom of the anode, forming anode mud, so correct. Choose C

The two gases can react with each other to form water under certain conditions, then these two gases are H2 and O2, Na and water react to form H2, Na2O2 and water react to form O2 so choose C

2. Chlorine water is produced by chlorine dissolving in water, and the reaction that occurs is Cl2 + H2O = HCl + HCl, which is an equilibrium reaction, and the concentration of each substance remains unchanged after reaching equilibrium.

This reaction occurs when left for a long time, 2HClo = HCl + O2 (the reaction is faster under photocatalysis).

As the HCl decreases, Cl2+H2O=HCl+HClO equilibrium proceeds to the right, and the HCl also increases, and the Cl ions increase.

It is placed in a sufficient amount of water to produce two gases, which in turn can react with each other to form water under certain conditions.

This sentence states that the two gases produced are H2 and O2

So Na reacts with water to form H2, Na2O2 reacts with water to form O2 equation: 4Na + 2H2O == 4NaOH + 2H2 (gas) 2Na2O2 + 2H2O == 4NaOH + O2 (gas) Saturated chlorine water reacts after being placed for a long time: 2HCl == 2HCl + O2 (gas) so HCl+ and Cl- are generated.

So choose C

The first gases generated are O2 and H2 and only two of C can produce both gases at the same time: Na2O2 and water to produce oxygen and Na and water to hydrogen.

The second product of Cl and water is HCl, which is unstable and decomposes, and only HCl is left, which is the Cl ion.

Affirmatively, Na202 should react with water to produce NaOH and 02, Na and water to form NaOH and H2, and hydrogen and oxygen to produce water. (Na2O reacts with water to produce only NaOH and no gas)

Question 2: It is the photolysis reaction of HCl, after HClL is placed for a long time, it will react with water to form HCL and 02, oxygen escapes, and Cl ions increase.

The two gases, in turn, can react with each other to form water under certain conditions.

It proves that there are h2 and o2

You can generate H2 only Na.

There is also a person who can produce O2 in water, showing that Na2O2 Cl water will react with water, Cl2+H20=HCl+HCl, or reversible, the reaction time is longer, 2HCl=2HCl+02 (gas), so there are more Cl ions.

Sodium peroxide is combined with water to produce oxygen.

Sodium is combined with water to produce hydrogen.

Hydrogen and oxygen can react to form water.

Chlorinated water turns into hydrochloric acid and hypochlorous acid.

Because plasma TVs are more popular.

First of all, the amount of hydrochloric acid required for complete titration is the same, but because phenolphthalein is used and methyl orange is used, so after the titration is completed, it is weakly alkaline and weakly acidic, that is, the amount of hydrochloric acid used is more than, and carbon dioxide is introduced into it, because the titration end point is a weak acid or weak alkaline environment, so the calcium carbonate precipitate formed will not be dissolved by hydrochloric acid, that is, the total amount of barium hydroxide is reduced, and the amount of hydrochloric acid required is less than and, and methyl orange is used with phenolphthalein, and it can be seen from the above that the amount of hydrochloric acid is obviously used more, Therefore, the volume size of hydrochloric acid consumed is < selection.

First of all, the endpoint pH of methyl orange is, phenolphthalein is about 8, through CO2 is equivalent to adding acid, the generated BAC3 is precipitated, does not affect pH, dilution twice has no effect, the relationship between 23 is caused by different endpoints, 14 is the same as 3 is very simple, the chemical dose point is PH7, then it is obvious that 8 is in the range of sudden transcendence, if the landlord does not have competition knowledge, it can be understood that the error is the amount of a drop, and when BaCO3 has been dissolved, so 314 is the same, and there are questions to ask.

Applicable to gases only.

B iron reacts with a sufficient amount of chlorine to produce only +3 iron ions, so 1molFe transfers 3mol electrons.

There are 7 protons in the c ammonium ion n and 4 protons in 4 h, for a total of 11 protons.

The concentration of sulfate in the solution is d, so the amount of sulfate ions can be found to be barium nitrate in addition to sulfate, but in this problem a new impurity nitrate ion is introduced, and the correct barium chloride solution should be used.

, introducing a new impurity, sodium nitrate.

: It doesn't say that H2O is gaseous, but it can't be calculated in this way.

C: The number of protons contained in 1molNH4+ is 11NA

D: The number of SO42- ions contained in mol l 1 sodium sulfate solution is the reaction with BA(NO3)2 to form nano3, which is also a soluble substance, which is equivalent to the formation of new impurities.

1...A, water is liquid.

The number of c-error protons is 11 NA

d error ion number is.

Mistakes should be made with bacl2 solution.

1a is obviously not true, it is 0 degrees Celsius under standard conditions].

b right. cnh4+ is 11 protons.

SO42 in DNA2SO4 - yes.

It's obviously not right.

A is the displacement reaction.

b can reduce the solubility of CO2.

D al can react with NAOH.

When the chemical equilibrium is reached, the product of the coefficient of the product concentration divided by the product of the power of the reactant concentration coefficient is a constant, which is set as k;

If you change the conditions, no matter how your concentration changes, in the example as in the question, under any conditions:

c(n2)]^2/ =q

If q > k moves in the opposite direction.

q = k does not move when it reaches equilibrium.

q < k is moving in the positive direction.

This is the standard basis for judging the balance movement. You didn't say exactly how much N2, H2 and NH3 concentrations changed, and no one could get an answer. Since the balance shifts to the left, it is certainly in line with the situation of q>k.

This is not how it is understood, nitrogen is added, the amount of reactants increases, and the equilibrium shifts to the right according to the principle of Le Châtea.

The chemical equilibrium shifts in the direction of the reverse reaction. Reason: The shift in chemical equilibrium does not fully offset the effects of changes in external conditions.

After adding N2 (pure) and reaching a new equilibrium, C(N2) eventually increases, but the addition of N2 makes V larger, but C(H2) and C(NH3) decrease, and the decrease in reactant concentration is greater than the decrease in product concentration, i.e., C(NH3) decreases more.

To put it responsibly, the answer is wrong.