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1g of pure calcium carbonate emits carbon dioxide.

Indicates that the impurities are comparable to calcium carbonate.

Both the mass and the gas emitted can be equal to calcium carbonate.

The molecular weight of KhCO3 is the same as that of calcium carbonate.

The same is true for CO2 emitted by the reaction.

So you can.

Let the chemical formula of the mixture be mco3 and the average molar mass of m is r, then there is mco3....co2

r+60...44

The solution is r=40, and the molar mass of Ca is 40, so it must be able to meet the carbonate of r=40, and only KhCO3 meets this condition, so the impurity in calcium carbonate is potassium bicarbonate.

From the equation, it can be seen that the CO2 mass is equal to 44*1 (R+60), if the molar mass of the impurity is greater than 100, then R+60 is greater than 100, so the CO2 mass is less than, on the contrary, if the molar mass of the impurity is less than 100, then R+60 is less than 100, so the CO2 mass is greater than.

The chemical formula of the reaction of KhCO3 with hydrochloric acid is KhCO3 + HCl = KCl + CO2 + H2O

This impurity needs to be able to produce as much carbon dioxide as calcium carbonate of the same mass.

KhCO3 can be because KhCO3 and calcium carbonate have the same molecular weight and the same mass fraction of carbonate.

If it is a other impurity, this requirement must also be met, that is, the amount of carbonate in the impurity is equal to that of calcium carbonate.

If there are multiple impurities, there must be at least one impurity with a carbonate content greater than the calcium carbonate, at least one impurity with a carbonate content less than the calcium carbonate, and the impurities that cannot produce carbon dioxide are regarded as having a carbonate content less than the calcium carbonate.

This impurity has to be satisfied:

1.It can react with hydrochloric acid, and the C in the impurities is released in the form of CO2.

2.The mass percentage of C in this impurity is the same as the mass percentage of C in calcium carbonate, and KhCO3 is OK.

First of all, this substance must contain carbonate or bicarbonate so that carbon dioxide can be generated, and secondly, the relative atomic mass of this substance must be the same as that of calcium carbonate, so that 1 gram will be generated in gram In addition, the mass fraction of carbonate or bicarbonate must be equal to the mass fraction of carbonate in calcium carbonate.

Because the relative molecular mass of KhCO3 and calcium carbonate is the same, both are 100

In addition, 100g of calcium carbonate can produce carbon dioxide (just write the chemical formula).

Similarly, by writing the chemical formula of the reaction of KhCO3 with hydrochloric acid, you can also know that 100g of KhCO3 can also produce carbon dioxide.

Impurities have CO3 2- and calcium carbonate has the same effect. The same is true for KhCO3.

Chemical formula: C10H15N

Structural formula: C6H5CH2CH(CH3)NHCH3 Structural formula: C6H5--CH2--CH(CH3)-NH—CH3

The reaction group is H on N, which can react with isocyanate, epoxy resin, etc.

The molecular formula contains a benzene ring, and the resin formed has the possibility of discoloration, and the resin has a certain flexibility and hardness), and has a certain solubility in aromatic compounds.

There is a certain reduction.

You give a structural formula, or a name, just a molecular formula, there are many structures, I don't know which one you want. I can't give it to you if I can.

CAO reacts with water to exothermic, the temperature increases, the solubility decreases, because the original solution is saturated, the solute will be precipitated, the solute in the solution is reduced, the solvent is not edged, so the mass fraction decreases instead of increasing. Because the solution refers to the solute and solvent, which does not include the precipitated part, the mass of the solution is reduced, so A is chosen

fe---feo

56% x=72%

2fe---fe2o3

56% y=80%

The mass fraction of the mixture KCLO3 may be greater than 1-80%=20% and less than 1-72%=28%.

1. Stupid search Fe2O3 + 3Co = high temperature = 2Fe + 3CO22. With car calendar caCO3 = high temperature = cao o + CO2 high temperature = 2CO

Ignition = CO2

Therefore, the sail family, the chemical reaction is 34, and c is selected

4al+3o2==2al2o3