English chemistry questions about molar mass

It is to ask you how much ammonia can be produced when nitrogen reacts with hydrogen.

Judge who overdoses.

The mass possessed by a substance as a unit of substance is called molar mass, which is denoted by the symbol m. When the quantity of a substance is measured in mol, the unit of molar mass is g mol, which is numerically equal to the relative atomic mass or relative molecular mass of the substance. For a compound, its molar mass is fixed.

The mass of a substance changes with the amount of matter.

The quantity of matter is a physical quantity, which represents a collection containing a certain number of particles, and the symbol is n. The unit of quantity of a substance is moles (mol). Scientifically, the collective containing Avogadro's constant (about a particle as a unit, called mole.

The number of particles contained in 1mol of different substances is the same, but the mass of 1mol of different substances is also different due to the different masses of different particles.

Isomeric reaction The volume remains unchanged before and after the reaction.

Let the amount of XO2 produced by the reaction be X mol

xy2(l) +3o2(g)= xo2(g)+ 2yo2(g)

x 3x x 2x

1) The amount of O2 is 3x, and the amount of total matter on the right side of the equation is 3x, because they are all gases, so the volume of O2 is 627ml

2) The molar mass of xy2 is conserved according to the mass, m(xo2)+m(yo2)-m(o2)] n(xy2).

m(xo2)+m(yo2) can be calculated by volume multiplied by density, and m(o2) can be calculated by multiplying the amount of oxygen by its molar mass m(xy2)=76

3) m(x)=3 (3+16) 76=12, m(y)=1 2 16 (3+16) 76=32, so x is carbon and y is sulfur.

1) The amount of gaseous substances before and after the reaction is unchanged, then the volume of gas under the same conditions is also unchanged, so the volume of oxygen is 672ml. (2) The total mass of the gas mixture after the reaction is g l=, and the mass of O2 can be obtained from the volume of O2 as, which is obtained by the law of conservation of mass, m(xy2)= , and the molar mass m = g mol is known from the relationship between the coefficients in the reaction formula.

There are three main ways to express the amount of matter with n.

1) n=n na, where n is the number of particles, na is Avogadro's constant, and na=

2) n=m ma, where m is the mass and ma is the molar mass. The magnitude of ma = the formula of the chemical formula of the substance (referring to the molecular weight or atomic weight).

3) For a gaseous substance, n = v va, where v is the volume of this gas and va is the molar volume. In general, the molar volume of a gas under standard conditions va = as long as it is under standard conditions, the molar volume of any gas is va =.

1) The quantity concentration of a substance is the number of moles of a substance per unit volume, formula: c=n v, unit: mol l

2) The molar volume of a gas is the volume of 1 mole of gas in a standard condition (the definition of a standard condition: a temperature of 0 degrees Celsius, a standard atmosphere). The molar volume of all gases in standard conditions is.

3) Molar mass is the mass of 1 mole of a substance, which is numerically equal to its relative molecular mass, for example: the molar mass of O2 is 32g mol.