To be fast Chemistry Summary How do you summarize chemistry?

CuSO4+2NaOH=Cu(OH)2 +Na2SO4 blue precipitate generation, the upper part is a clear solution Mass conservation law experiment.

Ca(OH)2 + CO2 = CaCO3 + H2O Clarified lime water becomes turbid, apply CO2 inspection and lime mortar to paint the walls.

Ca(HCO3)2δ CaCO3 +H2O+CO2 white precipitation, produces gas that makes the clarified lime water turbid, scale formation. Formation of stalactites.

HCl+AGnO3= AGCL+HNO3 Produces white precipitate, insoluble in dilute nitric acid The principle of testing Cl—.

Ba(OH)2+ H2SO4=BASO4 +2H2O produces a white precipitate, insoluble in dilute nitric acid The principle of testing SO42—.

BaCl2 + H2SO4 = BaSO4 + 2HCl Generate white precipitate, insoluble in dilute nitric acid Test the principle of SO42-.

Ba(NO3)2+H2SO4=BASO4 +2HNO3 Generate white precipitate, insoluble in dilute nitric acid The principle of testing SO42—.

FeCl3+3NaOH = Fe(OH)3 +3NaCl solution fades yellow and has reddish-brown precipitate.

AlCl3+3NaOH = Al(OH)3 +3NaCl has a white precipitate to form.

mgcl2+2naoh = mg(oh)2↓+2nacl

CuCl2+2NaOH = Cu(OH)2 +2NaCl solution fades blue and has a blue precipitate.

CaO+ H2O = Ca(OH)2 white bulk solid becomes powder, quicklime to prepare lime slurry.

Ca(OH)2 + SO2=CASO3 + H2O has a white precipitate to generate in junior high school.

Ca(OH)2+Na2CO3=CaCO3 +2NaOH has a white precipitate to produce industrial caustic soda and a small amount of laboratory caustic soda.

Ba(OH)2+Na2CO3=BaCO3 +2NaOH has a white precipitate to form.

Ca(OH)2+K2CO3=CaCO3 +2koH has a white precipitate to form.

AgNO3+NaCl = AGCl +Na NO3 white precipitate insoluble in dilute nitric acid (similar reaction to other chlorides) It is used to test chloride ions in solutions.

BaCl2 + Na2SO4 = BaSo4 + 2NaCl white does not dissolve in the precipitate of dilute nitric acid (other sulfate-like reactions) It is used to detect sulfate ions.

CaCl2+Na2CO3= CaCO3 +2NaCl has a white precipitate to form.

MgCl2+Ba(OH)2=BaCl2+Mg(OH)2 is formed with a white precipitate.

Fe2O3 + 6HCl == 2FeCl3 + 3H2O yellow solution.

Cuo + H2SO4 == CuSO4 + H2O blue solution.

AGNO3 + HCl == AGCL + HNO3 white precipitate.

BaCl2 + H2SO4 == BaSO4 + 2HCl white precipitate.

Ca(OH)2 + CO2 == CaCO3 + H2O white precipitate.

Ca(OH)2 + Na2CO3 == CaCO3 + 2NaOH white precipitate.

2NaOH + CuSO4 == Cu(OH)2 + Na2SO4 blue precipitate.

3NaOH + FeCl3 == Fe(OH)3 + 3NaCl reddish-brown precipitate.

cao+h2o==ca(oh)2

It's too much, little sister, look for it yourself, it's someone else's to find it, and you don't need to remember it if you look for it yourself.

Middle school chemistry is simple. The main thing is to memorize the element symbols.

Valency. Metal Activity Order Table.

Solubility of salt.

Characteristics of the displacement reaction.

Conditions for metathesis reactions. Sour. Alkali.

Salt. Basic overview. Also, there are no formulas to memorize in junior high school chemistry, they are all very simple, and you can quickly memorize them by relying on the rules.

1.Valency formula: potassium. Sodium.

Hydrogen. Silver +1 price. Fluorine. Chlorine.

Bromine. Iodine-1 valence. Calcium. Magnesium.

Barium. Zinc +2 valence.

Oxygen is usually -2 valence.

3 aluminum, 4 silicon, 5 valence phosphorus. That's it, let's not talk about the atomic cluster.

2.Table of solubility formulas for salt: potassium. Sodium.

Nitric acid. Ammonium salt soluble.

Hydrochloric acid does not dissolve silver. Argon. Mercury.

Sulfuric acid is insoluble in barium and lead.

The rest of the salts are insoluble. (Note: As long as it meets a soluble one, then the substance is soluble.) For example, KCL. This is k, too.

CL also complies. In fact, as long as it meets one, it would be fine. The hydrochloric acid in this is chloride salt.

There must be a high acre on the order table of metal activity, so I won't talk about it.

I hope what I said helped you and I wish you good results!

Upstairs, the solubility of NaCl at 20 is .

The addition of 40gnacl does not dissolve completely, so the mass of the solution is 100g+

Because the CO2 in b reacts with soda lime, the same goes for excluding b and answer c.

SO2 in D will react with soda lime, and NH3 will react with concentrated sulfuric acid, so the answer D is excluded so the answer is A

There is concentrated sulfuric acid and soda lime, so such a gas should have the property of not reacting with it.

Options for acidic oxides such as CO2 and SO2 are wrong, because acidic oxides can react with alkaline solutions, so there is only a pair. Choose A

According to the complete precipitation of barium ions, it can be concluded that n(SO4)2+=n(ba)2+=, so the amount of magnesium sulfate is m, magnesium sulfate = n*m=120*, and the mass of magnesium chloride is.

The amount of the substance of magnesium chloride is m m =

n Magnesium chloride n Magnesium sulfate = 2 1

1：caso4，2：ca（oh）2

3：ca+h2so4=caso4+h2

Ca(OH)2 + SO2 = CaSO3 (precipitation) + H2O, and excess SO2 generates calcium bisulfite.

Calcium sulfate, calcium hydroxide, calcium and sulfuric acid react to form calcium sulfate and hydrogen.

Calcium hydroxide is good for sulfur dioxide reaction to produce calcium sulfate, you write according to this.

a (relative atomic mass * number of atoms in the molecule of the element) relative molecular mass crude lead.

b Relative molecular mass * The amount of tung matter that is made of the tan stool complex.

4、a.The mass of the pure substance The mass of the mixture*100%b, the mass fraction of the element in the pure substance, the purity of the substance in the mixture.

100% = the mass of the element Total mass.

c=n vn=v(hcl) empty knowledge.

So c=n v=

2) Take out 500ml from the almost solution, and remove the solute N(HCl)=HCL==H++Cl-

Because 1mol of Keino HCl ionizes 2mol of ions.

So the total number of ions = 2*