High School Chemistry 1 5, High School Chemistry 1 Question

3-valent iron ions are hydrolyzed into iron hydroxide and hydrogen ions, and heating will enhance the degree of hydrolysis. Hydrogen ions and chloride ions combine to form HCl, which is heated and volatilized. Iron hydroxide will lose water and become iron oxide when heated.

Fe3++3H2O==Fe(OH)3+3H+(Equal sign reversible)2Fe(Oh)3==Fe2O3+3H2O

There is a heating symbol).

cuso4(s)+5h2o(l)=cuso4(aq)+5h2o(aq)；Discharge Q1kJ heat;

cuso4·5h2o（s）=cuso4（s）+5h2o（l）；Absorb Q2KJ heat;

Add the two equations as: CuSO4·H2O(S)=CuSO4(AQ)+5H2O(AQ);

Here we should also pay special attention to "the temperature of the solution decreases when the bile alum is dissolved in water", the reaction is endothermic, so it should absorb (Q2- Q1) [greater than 0] kj heat, so Q1 Q2, the correct answer is A. Trust me!

When the temperature of bile alum is dissolved in water, it is because it consumes a certain amount of energy to destroy the relatively stable structure of copper sulfate pentahydrate, and after the reaction, it can be approximately regarded as the formation of anhydrous copper sulfate dissolved in water and releases heat, that is, q2=q1-q3

i.e. Q2

cuso4·5h2o（s）=cuso4（s）+5h2o（l）；H=+Q2kJ, and CuSO4·5H2O(S) dissolves in water to absorb heat, so CuSO4(S)+5H2O(L)=CuSO4(AQ)+5H2O(AQ); Exothermic less than q2. Choose A

Hydrogen is made up of H2O

0,.5 Mo push out blindly is the quality of 1g. CO2 is grams. The carbon that can be obtained is 44 = mc=

mc+mh=

Then the mass of the oxygen is mo=

Launched as Mo c:h:o=9:10:2

ch2=ch-ch3+9/2o2=3h2o+3co2

As can be seen from the equation, at room temperature, the gas decreases, decreasing by 1+9 2-3=5 2

Hehe, write out the equation and calculate it according to the difference method!

ag2cro4 will electrify and delay the departure of two ag+.

Its Ksp formula is [AG] 2[CRO4] [AG2CRO4] Don't look at its KSP second smallest, but the square of the Ag+ concentration in the actual saturated solution is that number, so the actual Ag+ concentration is the largest.

The other two messy plums can be compared according to KSP, and the AG+ concentration of KSP is large.

1. The molecular weight of carbon monoxide and nitrogen is 28, which can be regarded as a gas, and the average molecular weight of oxygen = 29, and the ratio of the amount of matter can be found by the cross method is them: oxygen = 3:1, so the mass fraction of oxygen is:

32×1÷（4×29）= ；If the ratio of the amount of carbon monoxide and nitrogen is 1:1, then they are separated, then the mass fraction of oxygen in the mixture is: 16 (

2. 100ml of mixed gas is exactly combined with 150ml of hydrogen, and the average hydrogen is combined per ml of mixed gas. The average volume ratio of chlorine to hydrogen per ml is 1ml, and the average relative molecular weight of the mixed gas is (71 32) 2

Answer: Rotten ch4.

Analysis: The molar masses of CO2, CH4, N2 and O2 were 32 g mol, respectively. The molar mass of Xiangbei Tong CH4 is the smallest, that is, the amount of CH4 substance is the largest among the four of the same mass, and the number of molecules is the most numerous.

1999 Shanghai College Entrance Examination Chemistry Questions* 33The chemical group of carbonate copper ores (such as malachite, limestone, etc.) existing in nature becomes: acuco3·bcu(OH)2 (a, the difference is a positive integer, and A2b 2 is a positive integer, and (1) the malachite and limerite samples are respectively added with hydrochloric acid to completely dissolve, and the ratio of the amount of HCl substances consumed to the amount of CO2 substances produced:

Malachite is 4:1; The limestone is 3:1.

Their chemical composition is: Malachite: Stone Blue:

2) There is a sample of carbonate copper ore today, which is divided into two parts, A and B. Then, hydrochloric acid is added to completely dissolve sample A, resulting in a standard condition); Heat sample B to completely decompose to give 20 gcuO. Try to calculate and determine the chemical composition of the ore.

3) After the acid of a carbonate copper sample is completely dissolved, a standard condition is generated), and the cuo content in this ore sample is not less than g (4) The mass of a carbonate copper ore sample is a gram, and the quality of Cuo contained in it is g grams. After the acid is completely dissolved, the volume of CO2 produced (the standard condition of the god god) is v liters, and the relationship between a, v and g of copper-bearing ore samples is: a=

It's so difficult, I can see that B is correct.

c forgot what to ask, a, d is incorrect.

a As the reaction progresses, the pressure in m becomes smaller and n remains the same, so the reaction proceeds to a higher degree and the conversion rate is nm

It can be understood that in the case of the same temperature, m fixed volume n fixed pressure, try to solve it yourself?