How to distinguish sodium carbonate from potassium carbonate, except for the flame color reaction

Replacement is not possible (preferably flame color, followed by mass), sodium and potassium are both highly reactive metals at room temperature and violently react with water to form the corresponding hydroxide and hydrogen, so it does not react with solute (sodium carbonate).

The best method, and simple, is to add sodium tetraphenyl borate solution to potassium carbonate and sodium carbonate solution respectively, and the solution containing potassium will precipitate.

In a weakly alkaline medium, sodium tetraphenylborate solution is used as a precipitant to precipitate potassium ions in the sample solution to generate a white potassium tetraphenylborate precipitate, which is filtered, washed, dried and weighed. The potassium content of the fertilizer is calculated based on the quality of the sediment. The reaction formula is:

k++na[b(c6h5)4] →k[b(c6h5)4] ↓na+

No, because sodium and potassium are very reactive metals. Substitution doesn't work. However, we can try to use the same mass of acid to completely react the same mass of sodium carbonate and potassium carbonate, and look at the mass of the remaining liquid to judge.

1.Zinc uranyl acetate Zn[(UO2)3(CH3COO)8] is one of the most sensitive reagents for the identification of Na+. In a neutral or acetic acid solution, Na+ is combined with zinc uranyl acetate to form yellow-green crystals:

Naac·zn(AC)2·3UO2(AC)2·9H2O (yellow-green).

2.Potassium ions can be identified by hexanthoso cobalt complexes.

It is not impossible to displace, the activity of the metal is only effective in solution, and the preparation of cesium is replaced with calcium.

No, potassium and sodium will be reflected with water first, and if sodium is in a molten state, potassium may be replaced (high boiling point to low boiling point).

Weigh the same mass of sodium carbonate and potassium carbonate, react with sufficient calcium hydroxide respectively, take calcium carbonate precipitate after filtration, according to the chemical equation of the reaction between the two and calcium hydroxide, which one generates more precipitate, which is sodium carbonate.

The solubility of sodium bicarbonate in sodium chloride is low.

Sodium carbonate reacts with a small amount of hydrochloric acid to generate sodium bicarbonate and sodium chloride, no bubbles (CO2) to produce Na2CO3 + HCl = NaHCO3 + NaCl reacts with sufficient or excess hydrochloric acid to generate sodium chloride, carbon dioxide and water, and bubbles to produce Na2CO3 + 2HCl = 2NaCl + CO2 + H2O calcium carbonate and hydrochloric acid The reaction is carried out in two steps, the first step is to react to generate calcium chloride and carbonic acid, and this step is metathesis.

The second step is the decomposition of carbonic acid to produce carbon dioxide and water, and this step is the decomposition reaction.

It is a metathesis reaction, in which two substances that undergo metathesis exchange ions with each other in an aqueous solution and combine into substances that are difficult to ionize--- precipitation, gas, and water.

The reaction of sodium carbonate and hydrochloric acid produces both water and gas.

Reaction of sodium carbonate, sodium bicarbonate and hydrochloric acid.

If the amount of hydrochloric acid is less (hydrochloric acid is dropped into sodium carbonate solution): Na Co + HCl = NaCl + NaHCO No gas is produced.

If there is a sufficient amount of hydrochloric acid (sodium carbonate solution drops into hydrochloric acid): Na Co + 2HCl = 2NaCl + H O + Co There is gas production.

Sodium carbonate is a white, odorless powder or granule at room temperature. It is absorbent and gradually absorbs 1mol l of water (about = 15%) in the open air. Sodium carbonate is easily soluble in water and glycerol.

20 per 100 grams of water can dissolve 20 grams of sodium carbonate, when the solubility is the largest, 100 grams of water can be dissolved gram of sodium carbonate, slightly soluble in absolute ethanol, insoluble in propanol.

One of the identification methods of metathesis reaction is the formation of water or gas or precipitation.

First of all, it should be clear:

The essence of the metathesis reaction is that the two substances that undergo the metathesis reaction exchange ions with each other in the aqueous solution, and combine into substances that are difficult to ionize--- precipitation, gas, and water, so that the ion concentration in the lysate is reduced, and the chemical reaction is carried out in the direction of the decrease in the ion concentration in the land.

The chemical equation for the reaction of sodium carbonate with hydrochloric acid is: Na2CO3+2HCl==2NaCl+H2O+CO2

It is obviously a metathesis reaction.

A The use of hydrochloric acid can be distinguished, adding hydrochloric acid to form colorless gas is potassium carbonate, and no phenomenon is potassium chloride.

Therefore the troublesome finch is not chosen;

b Hydrochloric acid can be identified, and sodium carbonate is generated by adding hydrochloric acid to produce colorless gas.

The one without phenomenon is potassium chloride, so b is not selected;

c The use of NaOH can be identified, adding NaOH to produce a white precipitate of magnesium chloride, and no phenomenon of sodium chloride.

Therefore, C is not selected; d anions are chloride ions, can only be tested by flame color reaction, the flame color is yellow for the liquid cherry early sodium chloride, then the other substance is potassium chloride, so d is selected;

Therefore, choose D

A can be identified by hydrochloric acid, potassium carbonate is potassium carbonate is added to generate colorless gas, and potassium chloride is not selected;

b can be identified by hydrochloric acid, sodium carbonate is sodium carbonate is generated by adding hydrochloric acid, and potassium chloride is not selected if there is no phenomenon;

C can be identified by using NaOH, adding NaOH to generate white precipitate is magnesium chloride, and no phenomenon is sodium chloride, so C is not selected;

d anions are chloride ions, can only be tested by flame color reaction, the flame color is yellow for sodium chloride, then the other substance is potassium chloride, so d is selected;

Therefore, choose D