The amount of sodium bicarbonate reacted with calcium hydroxide

Excess calcium hydroxide produces calcium carbonate and sodium hydroxide, and the hydroxide in the aqueous solution comes from calcium hydroxide, and when the calcium hydroxide is in small amounts, the hydroxide in the solution comes from the hydroxide generated by the hydrolysis of carbonate. If the concentration of sodium bicarbonate is n, and the volume change of the solution before and after the reaction is not counted, then when calcium hydroxide is excessive, the concentration of hydroxide is n, and when calcium hydroxide is small, the concentration of hydroxide is less than n, because carbonate cannot be completely hydrolyzed, and its two-step hydrolysis is very small. So in these two solutions, hydroxide is more in (1).

There is no difference in the phenomenon, the difference in the ionic equation is who reacts first, so that the ratio of the reaction is different. The product is not the same.

Excess calcium hydroxide.

ca(oh)2 + nahco3 == caco3 + naoh + h2o

hco3-+ca2++oh-=caco3↓+h2o

All CO32- ions are converted into CaCO3 precipitate, and OH- is surplus, with a ratio factor of 1:1

Sodium bicarbonate excess.

ca(oh)2 + 2nahco3 == caco3 + na2co3 + 2h2o

2hco3-+ca2++2oh-=caco3↓+co32-+2h20

All 2OH- ions are converted into water, and HCO3- is left, with a ratio coefficient of 2:1

Question added: b

Similarly, sodium hydroxide should be in sufficient amount.

ca(hco3)2+2naoh == caco3+na2co3+2h20

ca2+ +2hco3- +2oh- == caco3↓+ 2h2o + co32-

Calcium bicarbonate in sufficient amounts.

ca(hco3)2+naoh == caco3+nahco3+h2o

ca2+ +hco3- +oh- == caco3↓+ h2o

HCO3- first with OH- to generate H2O with CO32-, if there is too much Ca(OH)2, then Ca2+ with CO32- completely generates a precipitate, if HCO3- is too much, and CO32- is generated, then CO32- is still left.

The chemical equation for the reaction of calcium bicarbonate with a small amount of sodium hydroxide is given below

naoh+ca（hco3）2=caco3↓+nahco3+h2o

Calcium hydroxide. In small amounts: 2NaHCO3 + Ca(OH)2=Na2CO3 + CaCO3 + 2H2O

In excess of calcium hydroxide: NaHCO3+Ca(OH)2=NaOH+CaCO3+H2O

When calcium hydroxide is in small amounts:

2NAHCO +Ca(OH) = NA CO +CACO +2Ho When calcium hydroxide is in excess:

NaHCO +Ca(OH) = NaOH+CaCo +H O Calcium hydroxide is a strong alkali and has a corrosive effect on ** and fabrics. However, because its solubility is not large, the degree of harm is not as great as that of strong alkalis such as sodium hydroxide. Calcium hydroxide can interact with acid-base indicator, purple litmus test solution is blue when it meets calcium hydroxide, and colorless phenolphthalein test solution is red when it meets calcium hydroxide.

CaCO3 and Na2CO3 are formed in small amounts

CaCO3 and NaOH are produced in excess.

When there is a small amount, there is more carbonate, and when there is more OH- in excess, the product will be different.

2NaHCO3 (excess) + Ca(OH)2 (small amount) = Na2CO3 + CaCO3 + 2H2O

NaHCO3 (a small amount) + Ca(OH)2 (excess) = NaOH + CaCO3 + H2O

Also: Ca(HCO3)2 (excess) + NaOH (small amount) = CaCO3 + H2O + NaHCO3

Ca(HCO3)2 (a small amount) + 2NaOH (excess) = CaCO3 + 2H2O + Na2CO3

When calcium hydroxide is in small amounts: 2NaHCO3 + Ca(OH)2=Na2CO3+CaCO3+2H2O

In excess of calcium hydroxide: NaHCO3+Ca(OH)2=NaOH+CaCO3+H2O

When calcium hydroxide is small in small amounts, with calcium hydroxide as the reference point, one mole of calcium hydroxide contains two moles of hydroxide, hydroxide to react with bicarbonate, two moles of bicarbonate are needed, of course, two moles of NaHCO3 are needed to generate two moles of water and two moles of carbonate, according to the combination of anions and cations, naturally, one mole of carbonate is combined with calcium ions to form calcium carbonate, and another mole of carbonate is combined with sodium ions to form sodium carbonate.

When calcium hydroxide is excessive, sodium bicarbonate is used as a reference point, and one mole of bicarbonate needs one mole of hydroxide, so only molar's Ca(OH)2 is needed, which is the same as the above analysis.

When calcium hydroxide is in small amounts: 2NaHCO+Ca(OH) = NaHCO+CaCo+2HO

In excess of calcium hydroxide: NaHCO+Ca(OH) = NaOH+CAo+HO

When calcium hydroxide is small in small amounts, take calcium hydroxide as a reference point, one mole of calcium hydroxide contains two moles of hydroxide, hydroxide to react with bicarbonate, two moles of bicarbonate are needed, of course, two moles of NaHCO are needed to generate two moles of water and two moles of carbonate, according to the combination of anions and cations, one mole of carbonate is combined with calcium ions to form calcium carbonate, and another mole of carbonate is combined with sodium ions to form sodium carbonate.

A small amount of NaHCO3 reacts with Ca(OH)2:

NaHCO3+Ca(OH)2=CaCO3 +NaOH+H2OThe NaHCO3 and Ca(OH)2 anti-juvenile spine sources of excess mental state field cavities should be:

2nahco3+ca(oh)2=caco3↓+na2co3+2h2o

Sodium excess: Ca(HCO3)2+2NaOH=CaCO3 +2H2O+Na2CO3

Ionic Equation:

ca2- +2hco3- +2oh- =caco3↓+ 2h2o+co3 2-

A small amount of sodium hydroxide stove: Ca(HCO3)2+NaOH=CaCO3 coarse spike + H2O+NaHCO3

Ionic Equation:

ca2- +hco3- +oh-=caco3↓+ h2o

The reaction equation of the reaction equation of sodium bicarbonate and calcium hydroxide is NaOH + NaHCO3 = Na2CO3 + H2O; The ionic equation is HCO +CA +OH = CA +HO. It means the reaction of bicarbonate with hydroxide ions to form water and carbonate, and the reaction of calcium ions combined with carbonate to form calcium carbonate precipitates.

Sodium bicarbonate, with the molecular formula NaHCO, is an inorganic salt, white crystalline powder, odorless, alkaline, soluble in water. It decomposes slowly in moist or hot air to produce carbon dioxide, which is heated to 270 degrees Celsius and completely decomposed. In case of acid, it decomposes strongly to produce carbon dioxide.

Preparation method of calcium hydroxide:

1. Lime digestion method:

After calcining the limestone into calcium oxide, it is digested by selection and water in a ratio of 1:(3) to generate calcium hydroxide material liquid through purification, separation and slag removal, and then centrifugal dehydration, dried at 150 300, and then screened (above 120 mesh) is the finished calcium hydroxide product.

caco3→cao+co2↑

cao+h2o→ca(oh)2。

2. Dissolve the reagent calcium chloride in water to prepare a 25% aqueous solution, heat it to 80, and then add the filtered 30% sodium hydroxide solution (which can exceed 30% of the theoretical amount) in batches to obtain calcium hydroxide, and the resulting slurry mixture is washed after filtration, and a large number of chloride ions are washed away with sodium hydroxide aqueous solution, and then washed with distilled water until the chloride ions are qualified.