I ve never been good at chemistry This test only scored 27 points What should I do Woo woo woo

Understand memory, cultivate interest, do more experiments, and do more test questions.

It doesn't matter, read the knowledge in the book thoroughly, and do some more information.

Select AD

a The original acetic acid is a weak electrolyte with weak electrical conductivity. Ammonia and acetic acid are added to react to form ammonium acetate salt, which is a strong electrolyte and has significantly enhanced conductivity;

b Since the original NaOH conductivity is relatively strong, the conductivity enhancement is not obvious after the addition of Cl2;

c Conductivity unchanged;

d The original H2S is a weak electrolyte with weak conductivity. The addition of Cl2 and H2S reacts to form HCl, which is a strong electrolyte with significantly enhanced conductivity.

I chose ABC because it is a strong electrolyte, so it does not change much.

D should not change (or weakly decrease) and then rise, because the word "a small amount" 2 determines that H2S will not react much, as a 2-element acid, it will pull the ionization equilibrium forward after the reaction, so that the free ions will not suddenly increase.

There is little change in DA, the ionization ability of acetic acid is already strong, and ammonia is introduced, even if ammonium acetate is generated, it is not very stable.

2.Let the solute in the solution after electrolysis be xmol, and the amount of solvent in the substance is 16(x+y) (40x+18y)= so x:y=1:10

3.The mass of sodium hydroxide in the solution obtained after the reaction is m, and the mass of water is n, and the mass fraction of oxygen is 80%

16m 40+16n 18) (m+n)=solution m:n=1::180

If 40 grams of sodium hydroxide are obtained, the mass of water in the solution is 180 grams.

According to the knowledge of the conservation of sodium, if 40 grams of sodium hydroxide are obtained, the original solution contains grams of sodium chloride, and the water consumed by electrolysis is x

2nacl+2h2o=2naoh+h2+cl236 80

x 40x = 18 grams.

The water in the original solution is 180 + 18 = 198 grams;

Volume of the original solution: (198+ ml = liters.)

Concentration of the substance of the substance of the original sodium chloride:

If you are not satisfied, you can see here.

(1) The algorithm and result of the first empty: (6mol l-2mol l) 2=2mol l min

The second empty algorithm and the result: 2mol l min 2=1mol l min (reason: the coefficient of SO2 and O2 is 2:1).

2) My question: It should be the reaction equilibrium after 2min, not the equilibrium after 2mol, right?

If the post-reaction reaches equilibrium, then: V(O2) is ,) is 1mol (l min), the reason is the same as above, the algorithm and result of the third space: 4mol L-V(SO2)*2(2min)=2mol L

In order, bubbles are produced on the surface of the iron wire, and the solution changes from colorless to light green copper wire without obvious phenomenon.

There is no obvious phenomenon in the insertion of aluminum wire and copper wire into hydrochloric acid.

fe+2hcl=fecl2+h2

3fecl2+2al=2alcl3+3fe

<> sixth question is not to tease Chi Chan to sell, and he almost forgot to argue a lot.