Chemistry Questions Thank You Very Much Chemistry Questions Thank you

B. should be chosen

The analysis is as follows: no blood red appears by adding KSCN, indicating that the solute in the solution is only Fe(NO3)2, N(NO3-) = x 4 - = (mol), so N(Fe)=N(Fe2+)==

After the reaction, KSCN solution was added, and there was no blood red, so it was Fe2. and it happens to be a complete reaction, so n(fe2) 2 n(no) n(hno3), and the solution is n(fe)=(choose b

Nitrogen altogether.

Produces nitric oxide.

Therefore, nitrogen in the solution.

And because of the presence of iron in the solution, all forms are ferrous nitrate.

fe（no 3)2---2n

Therefore, the amount of iron element matter is.

The answer is d.

A mg will react with hydrochloric acid to produce hydrogen, the mass of calcium carbonate in b is not 4.4 grams, so the mass is not equal on both sides of the mass, and the hydrogen produced by zinc and iron in c is not equal in mass.

The mass of gas produced by magnesium carbonate in d is grams.

A and D are both due to insufficient hydrochloric acid, and both will react to produce the same amount of hydrogen.

BC is a carbonic acid produced leaving 4g, or the same amount.

In the selection of DA, mg will react with hydrochloric acid to produce hydrogen, and the mass will be reduced.

The mass of carbon dioxide produced by the calcium carbonate reaction in b is not 4.4 grams, so the masses are not equal on both sides.

The amount of hydrogen produced by zinc and iron in c is not equal.

The mass of gas produced by magnesium carbonate in d is grams.

18mol l of sulfuric acid 50ml contains sulfuric acid 18 * 50 1000 =, diluted into 3mol l of sulfuric acid after the volume of the solution is.

The chemical formula is C3H8O3, then its relative molecular mass is -92-The ratio of the number of atoms of the carbon element to the hydrogen element is --3:8--The mass fraction of the oxygen element is.

The relative molecular mass is: 92

nc:nh=3:8

The mass fraction of oxygen is.

The aph is excluded by 4 1, indicating that it is an acidic substance.

Cathode: Anode = 2:1, a is suitable.

B: The reaction is complex, if it is a single reaction product, it is not equal to 2:1 but 4:1C: the anode and cathode products are 1:1, which is not compliant.

Correct answer: B. The cathode produces silver, and the anode produces oxygen!

Al+Fe2O3=Al2O3+2Fe2, Fe3+ +3SCN- =Fe(SCN Na2O2+2CO2=2Na2CO3+O24, hydrolysis reaction, CH3Cl NaOH---CH3OH NaCl (coheating with NaOH aqueous solution).

5. Elimination reaction, CH3CH2Cl NaOH---CH2=CH2+NaCl H2O (coheating with NaOH alcohol solution).

Iron Oxide:

2al fe2o3=al2o3 2fe

Ferric tetroxide:

8al 3fe3o4=4al2o3 9fe