Why the conversion of CO2 into chemical feedstocks such as methanol can help mitigate the greenhouse

CO2 is a greenhouse gas, and CO2 can be used as a raw material for the production of fertilizers, thereby reducing CO2 in the atmosphere to mitigate the greenhouse effect.

However, there is a problem with the production of fertilizers with CO2, which is the stability of the carbonic compounds in fertilizers. If CO2 is produced after a certain period of time after the application of chemical fertilizer, the purpose of reducing CO2 cannot be achieved.

a、co2g）+3h2

g）?ch3

oh（g）+h2

o(g) h=, at low temperatures, g= h-t?s 0, the reaction proceeds spontaneously, so a is correct;

b. For reversible reaction CO2

g）+3h2

g）?ch3

oh（g）+h2

o(g) h=, the forward reaction is an exothermic reaction with a decrease in volume, as can be seen from the figure, the curve reaches equilibrium first, and the amount of hydrogen increases during equilibrium, so the reaction rate should be increased when changing the conditions and the equilibrium moves to the reverse reaction, and the measures that can be taken are to raise the high temperature by hand, so b is correct;

c. The equilibrium constant is only affected by temperature, the reaction is exothermic, the temperature is increased and the equilibrium moves in reverse, the equilibrium constant decreases, the curve temperature is the highest, and the curve is second, so k k2

k1 is therefore c error;

d. The reaction is an exothermic reaction in which the volume of the gas decreases before and after the reaction, and when the reaction reaches the equilibrium state, the average molar mass of the gas in the container no longer changes, so D is correct

Therefore, c

1) The equilibrium state has not yet been reached at point A, the amount of reactant hydrogen continues to decrease, and the equilibrium moves forward to the middle hand, so the positive reaction rate is greater than the reverse reaction rate, so the answer is: greater than;

2) Calculate the reaction rate at different times separately: within 0 1min, v(h2=8mol-6mol

2l1min

1mol/（l?min）；1 Within 3min, v(h2=6mol-3mol

2l3min-1min

min）；3 Within 8 min, v(h2

3mol-1mol

2l8min-3min

min）；After 8 min, the chemical equilibrium state was reached, the forward and reverse reaction rates were equal, and the comprehensive rate was zero. Therefore, the reaction rate is the largest in 0 1 min and the smallest in 8 11 min, so the answer is: a; d；

3) The reaction rate of curve i increases, but the amount of hydrogen converted is small, and the temperature should be raised, because the reaction is exothermic and the temperature equilibrium moves in the opposite direction, which is not conducive to the conversion of hydrogen, so the Qulu Zheng line i is the increased temperature; Curve The reaction rate increases, the amount of hydrogen converted is more, and the balance moves forward due to the increase in pressure, so the pressure should be increased Therefore, the answer is: increase the temperature; Increase the pressure

1) Use the three-stage problem solving method to calculate Lao Ye.

co2g）+3h2

g） <

ch3oh(g) waiter did not shout +h2

o(g), start (mol l): 1 3 0 0

Change (mol l):

Equilibrium (mol l):

From the beginning of the reaction to equilibrium, the average reaction rate of hydrogen v(h2

mol?l-1

min-1, so the answer is:;

2) Conversion rate of hydrogen =

75%, so the answer is: 75%;

3) The equilibrium constant is equal to the product of the concentration power of the product divided by the product of the concentration power of the reactant, then k = c (ch

oh)c(h

o)c(coch

So the answer is:;

4) To make n(ch3

oh）/n（co2

Enlarge, the equilibrium should be shifted in the direction of the positive reaction, a due to the exothermic of the positive reaction, the elevated temperature equilibrium moves in the direction of the reverse reaction, then n(ch3

oh）/n（co2

decreases, so a is wrong;

b is filled with he(g), so that the pressure of the system increases, but for the reactive substance, the concentration does not change, the equilibrium does not move, n (ch3

oh）/n（co2

unchanged, so d is wrong so b is wrong;

c Separation of H2O(G) from the system, equilibrium shifted to the forward reaction method, n (CH3

oh）/n（co2

enlarged, so c is correct;

d Refill 1mol H2

If the concentration of reactants is increased and the equilibrium shifts in the direction of the positive reaction, then n(ch3

oh）/n（co2

enlarged, so d is correct

So the answer is: cd;

5) If the constant capacity of the closed container and the pressure of the whole system after the reaction is reduced compared with the previous one, although the addition of hydrogen is moving in the positive direction, the result of the equilibrium movement is to weaken this change, but not to eliminate the change of the potato seed, that is, although the equilibrium is moving positively, the amount of hydrogen is reduced on the basis of the increase, but CO2

g) at a small concentration, CH3

Increased concentration of OH(G), H2

When the concentration of o(g) increases and the equilibrium constant does not change, H2 reaches equilibrium

The concentration of the substance must be increased compared with before hydrogenation, so C1

c2 So the answer is:

Let the mass of carbon dioxide required be x,2CO2+6h2

Catalyst. c2h4+4h2o，88 28

x 28g88x=2828g

x=88gA: The mass of carbon that requires dioxane specialization is 88g

Note the concept bai

Transpiration ratio du: When plants consume 1 mol of water, photosynthesis fixes the amount of CO2 (mol) "We know that photosynthesis consumes water, and transpiration also consumes water.

A higher transpiration ratio means more CO2 is fixed when the same amount of water is consumed. The more CO2 is fixed, which means that the more organic matter is synthesized, that is, the photosynthesis is stronger, and more water is used. So it is inferred that:

The greater the transpiration ratio, the more water is used for photosynthesis than transpiration. That is, the higher the transpiration ratio, the more drought-tolerant the plant is, because it has less transpiration, more photosynthesis, and high water efficiency, and only requires relatively little water to synthesize a certain amount of organic matter.

Sort out this logical relationship, and then it's easy. The transpiration ratio of the European fern is greater than that of heather, so it is more drought tolerant, and drought has less effect on it and more on heather. The two analyses you gave have the same meaning, and the expressions are much the same.

The effect of transpiration on photosynthesis is mainly due to the fact that when cells lose more water during transpiration, the stomata will close in order to retain water, so the CO2 intake will also decrease and the photosynthesis rate will decrease. The extent of this effect is different for different species of plants and is related to their habits.

1) According to the figure, the higher the temperature, the lower the yield of methanol, indicating that the reaction is an exothermic reaction, and the higher the pressure, the higher the methanol yield, so the answer is: cooling and pressurization;

2) Set CO2

The conversion rate is x, the amount of the starting substance is 1, and the complete conversion to methanol is x, which is calculated using a three-stage formula.

co23h2

ch3oh+h2

oStart 1 3 0

Conversion x 3x

Balance 1-x 3-3x x then x

25%, so the stove imitation x=25%, the lower the temperature, the smaller the pressure, the smaller the reaction rate, the equilibrium moves in reverse, and the conversion rate of carbon dioxide decreases, so the answer is: 25%; Minish; Minish;

3) Utilize the three-stage formula, CO2

3h2 ch3

oh+h2o

Start (mol l) 0 0

Transformation (mol l) next to which cryptofibrils.

Equilibrium (mol l):

So k=c(ch

oh)?c(hoc(co

c(h, so the answer is:;

4) Reaction CO2

g）+3h2

g）═ch3

oh（g）+h2

o(g) can be determined by 2h2

g）+o2g）=2h2

o（g）；②co（g）+2h2

g）=ch3

oh（g）；③2co（g）+o2

g）=2co2

g）；Replace ( +2 -1

According to Geis's law, the heat of reaction is 1

kj mol, and then write the thermochemical equation as CO2G) +3H2

g）═ch3

oh（g）+h2

O(g) H= kJ mol, so the answer is: CO2G)+3H2

g）═ch3

oh（g）+h2

o（g）△h= kj/mol；

a. Chemical equilibrium constant k = product of the power of the equilibrium concentration coefficient of each product.

The product of the power of the equilibrium concentration coefficient of each reactant.

c(choh)?c(ho)c

h)?c(co, so the chemical equation for this reaction is 3h2(g)+CO2(g)?CH3OH (G) + H2O (G), the temperature increases, the K value becomes smaller, so H 0, so A is wrong;

b. Density of the gas mixture = m

v,m is conserved before and after, v is constant, so when the density no longer changes, the reaction does not necessarily reach the equilibrium state, so b is wrong;

c. When equilibrium, other conditions remain unchanged, and the use of catalyst will not cause the movement of chemical equilibrium and will not affect the conversion of CO2, so C is wrong;

d. In a closed container with constant temperature and constant capacity, when the concentration of H2 is increased, the chemical equilibrium is moving to the right, and the carbon dioxide conversion rate is increasing, so D is correct

Therefore, choose D