Chemistry compulsory one knowledge in senior one for help, thank you

The difference method is ......

In the mixture, only sodium bicarbonate loses mass when heated, and sodium bicarbonate is decomposed into sodium carbonate when heated, water, and carbon dioxide.

Equation 2NaHCO3 == (heated) Na2CO3 + CO2 +H2O

Because water and carbon dioxide are always produced at a ratio of 1:1.

Therefore, the amount of water and carbon dioxide can be directly set as x mol, then x * 18+44)==

Solution x==

So the amount of water and carbon dioxide is the same.

According to the chemical reaction equation, the ratio of the measurement numbers can be obtained, and the amount of sodium bicarbonate is so m(naHCO3)== * 84g mol==, and the total mass is 5g, so m(na2CO3)== is done

Sodium bicarbonate is thermally decomposed into sodium carbonate and water and carbon dioxide.

It turns out that there is xmol sodium carbonate and ymol sodium bicarbonate.

2NaHCO3=Na2CO3+H2O+CO2, the amount of H20 and CO2 is y 2mol The water and carbon dioxide produced by decomposition have run away.

So 18*y2+44*y2=

There is also the original 106x+84y=5

The solution is y=so it turns out that the mass of sodium carbonate is.

CO2 sulfur dioxide is dissolved in water to form sulfurous acid, which is a weak acid and cannot react with barium chloride (strong acid to weak acid).

NH3 and sulfurous acid form salts, which can be precipitated with barium chloride to form barium sulfite.

H2S reacts with sulfur dioxide to form sulfur elemental precipitates.

NO2 oxidizes sulfurous acid to sulfuric acid, because sulfuric acid and hydrochloric acid are both strong acids, so sulfuric acid can form barium sulfate precipitate with barium chloride.

CO2 cannot.

Hope it helps.

co2.。。Obviously, it doesn't produce baso4... It just doesn't oxidize 4-valent S to 6-valent.

Are you asking about the number of water molecules and hydrogen atoms?

Number of water molecules: moles multiplied by Avogadro's constant.

Number of hydrogen atoms: 1 mole multiplied by Avogadro's constant (find the specific data in the book).

400ml of hydrochloric acid per liter was added to the mixture, which just dissolved the mixture, and released 224ml of gas under standard conditions, indicating that iron reflected all other valence states of iron to form Fe2+, and added KSCN solution to the addition solution colorless blood red, indicating that there was only Fe2+ in the solution, so there was only FeCl2 in the solution

According to the conservation of charge: FeCl2=Fe2+ +2Cl-N n=

so2+naoh=nahso3

nahso3+naoh=naso3+h2onahso3

So the ratio of sulfite to bisulfite is only :(:1

The oxidation is not so strong.

It should be sulfite ions and bisulfite ions, right?

Regardless of the hydrolysis reaction of the two acids, the ratio is.

Sulfite ions.

Bisulfite ions.

Write out the ion equation, considering that sulfate ions and bisulfate ions are generated later, so the reactants should be oxygen, hydroxide ions, sulfur dioxide, and the products should be sulfate ions, bisulfate ions, and water. The ratio of the equation coefficient of hydroxide ion to sulfur dioxide is 5 to 3, and then the trim equation is enough, and the answer seems to be 2 to 1

The reason for choosing D is that SO2 and CO2 are both acidic gases, which will react with sodium hydroxide.

It reacts with clarified lime water to form a white precipitate.

It was found that SO2 was reducing, and the acidic potassium permanganate solution was introduced to remove SO2 (CO2 does not react), and then CO2 was tested

Analysis:1. a: c=1000 w% m =10 w m (wrong) b: m=nm=c*v*10-3*m=10 w m*10-3*m=v w 100 (right).

c:c=1000 w% m w =cm 1000 (false)d: c=n (v*10 -3)=m (mv*10 -3)=1000m vm (right).

2。 nacl---agno3 mgcl2---2agno3 alcl3---3agno3

vc1 3c vc2 2c vc3 c

From the above formula: c1:c2:c3= 9:3:1 So choose c to wish learning progress!!

Your first question b should be m=v w. v is the total mass of the solution, and we set it to m, i.e., v = m, m = mw

The equation for the second question of magnesium chloride should be mgcl2, one volume of aluminum chloride corresponds to three volumes of silver nitrate, just push it proportionally, I won't count it.