High One Chemistry Option 7, Senior One Chemistry Choice

s changes from +6 valence to +4 valence, giving 2 electrons.

From the ratio of the amount of the consumed element to the amount of acid is 1:2, the element gives 4 electrons, so it is expressed as a valency of +4 valence.

The valency of S in D H2SO4 to SO2 changes from 6 to 4 and the ratio of the amount of matter is 1:2, so it is 2*2=4

Let the metal q valency +x

Q+H2SO4---Q2(SO4)X+SO2+H2O, if the SO2 coefficient is also X, then the S valency decreases by 2X, then the Q2(SO4)X coefficient is 1, then the H2SO4 coefficient on the left side of the equation is 2X, and the Q coefficient is 2

2/2x=1/2x=2

The upstairs is so powerful, the landlord should have this answer.

a.Mistake. This is because the adapted strip hood is a standard gas (atmospheric pressure, 0 °). At room temperature and pressure, the molar volume of the gas is not equal to.

b.Mistake. 1 ammonia molecule contains 4 atoms. So 1mol of ammonia should contain 4mol of atoms, then according to n=n na. Contains atomic number 4Na.

c.That's right. 32g of oxygen is 1mol, and 1 oxygen molecule contains 16 electrons, so the number of electrons contained in 1mol of oxygen is 16na

d.Mistake. You can use the limit method, assuming that 28g is all co, or co2 to calculate stupidly, you can get the answer you want.

a correct, at room temperature and pressure, compared with the standard condition, the pressure is the same, the temperature increases, so the molar volume of the gas increases, then the amount of the gas should be less than.

b False, the atomic number of 1mol NH3 should be 4Na

c Correct, 32g oxygen is 1mol, 1 oxygen atom contains 8 electrons, then 1 oxygen molecule is 16, 1mol is 16mol, so the number of electrons is 16na

d False, this question can only be assumed by the limit assumption, 28g of CO is 1mol, 28g of CO2 is about , so the number of molecules can only be between 1Na.

Based on the information you provide, there is certainly not only one answer to this question. You turn your mind shut up and see if you have copied the question incorrectly.

The blood tonic oral liquid mainly contains ferrous ions, and vitamin C is a reducing agent, which can prevent ferrous ions from being oxidized, thereby promoting the absorption of ferrous ions.

The reducibility of br- < the reducibility of Fe2+.

A, n(Cl2) : N(Febr2) = = 2 : 5, indicating that Cl2 is not enough to oxidize all Fe2+, so the ion equation is only Cl2 ferrous oxide ions, which is correct.

B, n(Cl2): N(Febr2) = = 3 : 5, indicating that Cl2 can oxidize all Fe2+, and there are 6-5 = 1 part of Cl atom to oxidize Br-, so the ion equation should be:

3cl2 + 5fe2+ +br- = 5fe3+ +1/2)br2 + 6cl-

Convenient**, write the br2 premolecular coefficient as 1 2, should be multiplied by 2, wrong.

c、 n(cl2) :n(febr2) = 1 : 1

After all Fe2+ is oxidized, there is still half of the Cl atom to oxidize Br-, and the ion equation should be:

cl2 + fe2+ +br- = fe3+ +1/2)br2 + 2cl-

Correct d, n(cl2): n(febr2) = = 3 : 2

Exactly oxidize all the ions, and the ion equation is as follows:

3cl2 + 2fe2+ +4br- = 2fe3+ +2br2 + 6cl-

Correct so, the incorrect is b

The answer should be B.

When chlorine gas is introduced into ferrous bromide solution, it is oxidized by chlorine because both ferric and bromine ions are reducible.

When there are two reducing ions in the solution, the more reducible ones are oxidized first, and then the less redox ones.

Ferrous ions are very reducible, certainly stronger than bromine ions, so the ion equation in b can only be written like that if the bromine ions are oxidized first.

a, you should be fine, it is the first step of ferrous ion oxide.

It is related to the amount of chlorine gas introduced, and when a reaction occurs, the amount of reaction is different, and the ion equation is generally different!

Because according to the reducibility of Fe2+>br-, Cl2 oxidizes ferrous ions first, and then replaces Bri-, so B is definitely wrong, a mol Febr3 needs mol Cl2 to oxidize Fe2+, and a mol Cl2 to oxidize Br-

According to it, and the number of atoms contained in it is equal and a is an oxygen element.

It can be concluded that AM is O2

Then * 2 = * n=

It is concluded that the relative atomic mass of b is 14, and the wide obscure b is an element n.

So the name b is nitrogen.

At the same time, we can know that m=n=2

In addition, I don't understand what the conditional volume ratio given in the title is 2:3, which may confuse you, after all, the gas element of n should only be n2

If we have to use this condition, according to the ideal formula pv=nrt,p,r, when there is a certain time, Zheng slip n,v are proportional, and the ratio of the amount of their matter can be obtained as 2:3....But it didn't work.

1. The number of outermost electrons of the atom of element A is A, the number of electrons in the secondary outer shell is B,-- B can be 2 or 8

The number of electrons in the m shell of element b is (a-b), and the number of electrons in the l shell is (a+b) - so b cannot be 8, it can only be 2, and element b has k, l, m3 layers, so l shell has 8 electrons, i.e. a is 6

So, a is 2,6, i.e., the o element.

b is, 2, 8, 4, i.e. the si element.

The compound is SiO2 and the impossible property is ---A

It is not possible for A to react with water, --- SiO2 does not react with H2O.

b reacts with carbon ---SiO2 + 2C = high temperature = Si + 2Co

C reacts with sodium hydroxide---SiO2 + 2NaOH = Na2SiO3 + H2O

D reacts with sodium carbonate ---SiO2 + Na2CO3 = high temperature = Na2SiO3 + CO2

2. For the reversible reaction 4NH3 (G) + 5O2 (G) = 4 NO (G) + 6H2O (G) The following statement is correct ---a

When a reaches chemical equilibrium, 4V positive (O2) = 5V inverse (NO)--pair, which conforms to the coefficient ratio of the reaction.

b If XmolNH3 is consumed while generating XMOLno per unit time, then the reaction reaches an equilibrium state --- wrong, both are positive reaction rates, and even if they are not balanced, they are also in line with this relationship.

When the chemical equilibrium is reached, if the volume of the vessel is increased, the positive reaction rate decreases, and the reverse reaction rate increases --- wrong, and the volume is increased, which is equivalent to decompression, and the forward and reverse rates are reduced.

D The chemical reaction rate relationship is 2V positive (NH3) = 3V positive (H2O) - false, which does not conform to the coefficient proportional relationship, it should be, 3V positive (NH3) = 2V positive (H2O).

First **a:a If it is the third period, the number of electrons in the secondary outer shell b is equal to 8, then the number of electrons in the l shell of element b will be more than 8, contradictory, so a is the second period element, b 2;The number of electrons in the L shell by element B is A+B, and the L layer should be the secondary outer shell of element B, so A 6, so that A is oxygen and B is silicon.

A and B form silicon dioxide, which is an atomic crystal with high melting point and high hardness, insoluble in water and acid, and soluble in sodium hydroxide to form sodium metasilicate (sodium silicate, bubble alkali).

Choose C for the first question

The number of electrons in the m shell of element b is (a-b), and the number of electrons in the l shell is (a+b).Then a + b = element subouter electron number is b = is o element b is si element. The compound is SiO2

SiO2 + 2C = High temperature = Si + 2Co

SiO2 + 2NaOH = Na2SiO3 + H2O (i.e., NaOH reagent bottles cannot be corked with glass).

SiO2 + Na2CO3 = High temperature = Na2SiO3 + CO2 (strong acid to weak acid).

--When the chemical equilibrium is reached, 4V positive (O2) = 5V inverse (NO) --Yes, there is a condition of "reaching chemical equilibrium", so it can be said that the coefficient ratio of the reaction is conformed at the same time.

b This is also the case until the chemical reaction is not equilibrated.

c increases the volume, which is equivalent to decompression, and the forward and reverse rates both decrease (this is the main cause), and 4+5 is less than 4+6

As the volume increases, the reaction moves towards the positive reaction, and the speed accelerates as the secondary cause.

d is wrong, does not conform to the coefficient proportional relationship.

The volume occupied by O2 (oxygen) is about.

Wrong, it's under standard conditions.

N2 (nitrogen) contains Avogadro's constant nitrogen molecules.

False, under standard conditions.

c.In standard condition, the quality of the water is about 18g

False, water is not a gas under standard conditions.

CO2 and HCl under the standard condition contain the same number of molecular pairs, both of which are moles.

In d a, the standard condition should be added, and the standard condition b should also be added, and the standard condition c water is a liquid, not a gas, so d is selected