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The relative density of organic matter to H2 is 28, that is, the molar mass of the organic matter is 28 times that of H2, so m = 2x28 = 56, the mass is, the amount of the substance n = m m =, there are 2 kinds of products after the combustion of hydrocarbons, namely H2O and CO2, the weight gain of concentrated H2SO4, that is, the mass of water is, from this it can be calculated that the amount of water is , the weight of NaOH solution is increased, that is, the mass of CO2 is, from this it can be seen that the amount of CO2 is that, according to the conservation of elements, there are c and h in the hydrocarbon, So the molecular formula of this hydrocarbon should be C4H8

1. cxhy+(x+y/4)o2=xco2+y/2h2o1 x y/2

n1 n2 sulfuric acid weight gain is water weight n2=

So y=8CO2 is absorbed by Naoh N1=

So x=4 results in c4h8

2.Because the relative density of the modified organic matter to H2 is 28, that is, the molar mass is 28 times that of H2, so m = 2x28 = 56, the mass is, the amount of the substance n = m m =, there are 2 kinds of products after the combustion of hydrocarbons, namely H2O and CO2, the weight increase of concentrated H2SO4, that is, the mass of water, from which the amount of water can be calculated as, the weight increase of NaOH solution, that is, the mass of CO2 is, from which it can be known that the amount of CO2 is , according to the conservation of elements, there are c and h in the hydrocarbon, So the molecular formula of this hydrocarbon should be C4H8

3.The weight gain of concentrated sulfuric acid shows that the water vapor is grams, the weight gain of sodium hydroxide shows that there are grams of CO2 The relative vapor density of H2 is 28, which indicates that the molar mass of this hydrocarbon is 56 Bring in the formula CXHY+(x+y

4) O2=xco2+y 2H2O, which means C4H8

(1) Because the amount and concentration of the substance remains unchanged after the same volume is mixed, and the volume becomes twice as large as the original, the amount concentration of the substance is 1 2.

2) This question is not comparing the ionization equilibrium constant of acid, kw is the ionic product constant of water, which is only affected by temperature and not by the type of solute in it.

3) Option b is correct. It should be understood as such:

Because temperature changes are ignored, the above equation is a constant. So it doesn't change. In the same way, dilute a glass of acetic acid solution, and the fraction will not change.

The answer is C, because the product of the complete reaction between CH3COOH and NaOH is CH3COONA, which is a strong base and weak acid with a pH of >7, which is not equal to 7.

(1) You are wrong. Because of the equal volume mixing, the Ca2+ concentration is halved.

2) KW is the ionic product of water, which remains constant as long as the temperature is fixed.

3) In option b, multiply the top and bottom by c(h+).It becomes C(CH3COO-)*C(H+) C(CH3COOH)*C(OH-)*C(H+)=ka KW

Both constants are only related to temperature, the temperature does not change, and the ratio does not change.

1. Because the volume of the two solutions becomes twice as large as the original after the equal volume is mixed, the concentration is halved.

2. KW is not an ionization constant, but the ion product of water, which is only related to temperature and has nothing to do with the type of solution.

3. The ionization constant ka=c(h+)*c(ch3coo-) c(ch3cooh) is not the equation in the title, so it is not contradictory.

Obviously, magnesium sulfate can't be used, because sodium carbonate is only a small amount (impurities), and magnesium carbonate is slightly soluble in water (not insoluble in water), and the resulting small amount of magnesium carbonate cannot precipitate at all (magnesium hydroxide precipitation must be heated to promote hydrolysis, which is off-topic).

Magnesium bicarbonate is soluble in water, which does not take into account (in addition, magnesium bicarbonate does not double hydrolyze, because both magnesium and bicarbonate ions bind OH-).

Another reason is that magnesium sulfate contains magnesium ions and sulfate ions, and since these two ions cannot be precipitated out after being added, these two impurity ions will definitely be mixed into the solution.

Personally, I think that the best way to prove that sodium carbonate is mixed is to add a small amount (note that it can only be a small amount) of clarified lime water, because calcium bicarbonate is soluble in water, while calcium carbonate is insoluble in water.

Is it the final answer question? 2Na2O2 + 2H2O ==4NaOH + O2, where the oxygen element in sodium peroxide is -1 valence, so it is in the middle valence of the oxygen element, so when the redox reaction occurs, it is -1 valence O itself to gain and lose electrons. So both oxidizing agent and reducing agent are Na2O2.

So the answer is:

1. Oxidant Na2O2 Reducing agent Na2O22, let the gas generated be VL, because the mass of Na2O2 is 39g, so N(Na2O2) = 39g (78g mol) =

According to the title, there are:

2na2o2 + 2h2o ==4naoh + o22 mol

vl so the solution is: v=

So the volume of oxygen produced under the standard condition is.

A, the conductivity of the solution is not only related to acetic acid, but also related to Na, and the concentration of Na has been increasing before the shed.

b, the hydrolysis reaction of Huiru ethyl acetate has nothing to do with the conversion rate.

c, ammonium chloride is a weak electrolyte, hydrochloric acid is a strong acid, and ammonium chloride will not change significantly when adding water.

d, the degree of ionization of water can be seen and rented out by looking at the curve.

A and B are isomers that, after hydrolysis, form C, D, and E, F, respectively.

There are 2 substituents on salicylic acid, one can react with acid and one can react with alcohol. So C, D, and E, F are acids and alcohols, respectively.

c can occur the silver mirror reaction. Continuous oxidation can produce the same molecular mass as d. But different kinds of organic matter.

C is formic acid, D is ethanol; E is acetic acid and F is methanol.

7 C's have been consumed to obtain salicylic acid, indicating that C and D have a total of 3 C's, C can only be formic acid and D is ethanol.

h 0, the reaction is exothermic reaction, the higher the temperature, the faster the reaction rate, so option e is wrong; Solids generally do not consider the influence on volume and pressure, two COs generate one CO2, and the total volume is reduced, so the container volume should be gradually reduced and then unchanged. Option d is correct. For vessels with variable volumes, the reaction reaches equilibrium if the volume, pressure, and density do not change, so ABC is correct.

Therefore, ABCD is chosen.