A chemistry problem, Comparison of boiling points, Thank you.

It should be pure iron, because pig iron contains a lot of C, which will make the substance impure and the boiling point will increase.

The boiling point of the type chain of the following compounds is more correct.

a.n-butanol, butanone, ether.

b.n-butanol, ether, butanone.

c.Butanone, n-butanol, and B travel ether.

d.Butanone, ether, n-butanol, Bu Zhensun.

Correct Answer: a

Answer] :d H2O molecule contains H—branches or land O....H-hydrogen bonding, compared with the same H2Se and H2S molecules, has an abnormally high boiling point, heat of melting and heat of evaporation, while heavy water has a higher boiling point than water due to the higher mass of O.

This is a question about the dependence of the solution, which is more complex and complex.

The simplest way to understand this is this: solutes reduce the water molecules on the gas-liquid contact surface.

The number of mass points reduces the volatility of water.

Among them, the electrolyte dilute solution (in this case, table salt) is more dependent than the non-electrolyte.

In this case it is glucose.

The dependence of dilute solutions, so the boiling point of both judgments is higher than 100 degrees, and the boiling point of salt water is higher than that of glucose water.

Solution: Grasp the amount of sulfuric acid in the dilution process does not change, i.e.

c1v1=c2v2→18mol/l *(100/p)*10^3l=9mol/lv2→v2=（

Assuming that the concealment width of the diluted solution is g ml, then.

The mass of the diluted solution is as follows: ( g ml = ( g = (200 p)g.)

Then the mass of water added: (200 p) g-100g volume of added water: [(200 p)-100] ml

So the volume is less than 100ml

Let the density at the beginning be P1, the density after adding water is P2, and the volume of water added to the abrasive is V, then (100g P1*18mol L) = 9mol L

v=p2 5p1-1 10, when p2=p1, v=100ml, but p2 is less than p1, so v is less than 100ml

To do this kind of problem, you don't need to calculate the spring brother early, because p is greater than 1 (actually, so v is less than 100, add water.

It is diluted successfully at 2v, and the volume of water added is naturally less than 100 ml of dust bushes.

Oxygen is sufficient, so there is no iron in the solid.

Limit method, let all FE2O3

then Fe2O3 8g is generated

Hence the inclusion of FEO

Whereas, with complete combustion, FEO does not exist alone, together with FE2O3 FE3O4 is formed, so the answer is C

The iron atom is.

The oxygen atom is. The ratio of ferric oxygen is greater than the proportion of Fe3O4, and the proportion of less than Fe2O3 is only consistent with C.

The average molecular formula of the gas mixture of C2H4 and C2H2 is C2Hy, then C2HY+(2+

Then 2 + solution gives y=

So yes. Solution x = choose b

and C2H4 are both 2 C, let a total of 1mol, then 2molCO2 is generated after combustion, there is, o is conserved, H2O is , then H is, addition is 1molC2H6, 6molH, so poor, it is necessary.

Assuming all the ethylene, it will be 3 times. Suppose all acetylene, to double. Cross to get ethylene to acetylene = 3:2

Assuming that the original 3mol ethylene and 2mol acetylene are originally required, 3mol hydrogen and 4mol hydrogen are required respectively. So a total of 7mol

The mass of MGSO4 is 10%*120==12 g, and the remaining material type is g

Then mgSO4 : H2O==12 120 : Cover and rent lead 18==1:7 i.e. x=7