Laws of Definite Proportions, Multiple Proportions

Q.

Determine the empirical formula of an oxide of iron which has 69.9% iron and 30.1% dioxygen by mass.

Q.

Two elements A and B form compounds having formula AB₂ and AB₄. When dissolved in 20 g of benzene (C₆H₆), 1 g of AB₂ lowers the freezing point by 2.3 Kwhereas 1.0 g of AB₄ lowers it by 1.3 K. The molar depression constant for benzene is 5.1 Kkg mol⁻¹. Calculate atomic masses of A and B.

Q. 27.molarity of 29% w/W H2so4 solution whose density is 1.22 g/ml

Q. Two elements, X (Atomic mass 16) and Y (Atomic mass 14) combine to form compounds A, B and C. The ratio of different masses of Y which combines with fixed mass of X in A, B, and C is $1:3:5$. If 32 parts by mass of X combines with 84 parts by mass of Y in B, then in C 16 parts by mass of X will combine with

1. 14 parts by mass of Y
2. 42 parts by mass of Y
3. 70 parts by mass of Y
4. 82 parts by mass of Y

Q.

Pls help me by providing practice Questions for concentration terms

Q. 12 gram of an alkaline earth metal gives 14.8grams of its nitride.The atomic mass of the metal is

Q.

How many grams of NaOH should be dissolved to make 100cm^3 of 0.15 molar sodium hydroxide solution?

Q. Element X forms five stable oxides of formula - $X_{2}O,XO,X_2{O}_3,X_2{O}_4,X_2{O}_5$. The formation of the oxides explains:

1. Avogadro's law
2. Law of partial pressure
3. Gay-Lussac's law
4. Law of multiple proportions

Q. A sample of calcium carbonate $\left(CaC{O}_3\right)$ has the following percentage composition $Ca=40\%;C=12\%;O=48\%$
If the law of constant proportions is true, then the weight of calcium in $4\text{g}$ of a sample of calcium carbonate from another source will be

1. $0.016\text{g}$
2. $0.16\text{g}$
3. $1.6\text{g}$
4. $16\text{g}$

Q.

If two elements can combineto form more than one compound, the masses of one element that combine with a fixed mass of the other element, are in whole number rato.

(a) Is this statement true ?

(b) If yes, according to which this law.

(c) Give one example related to this law.

Q. Calculate the molarity and molality of a solution made by mixing equal volumes of 30% by weight of H2SO4 (density = 1 218 g/ml) and 70% by weight of H2SO4 (density = 1 610 g/ml)

Q. Dalton's theory included which idea?

1. Atoms of different elements always combine in one-to-one ratio
2. Atoms of the same element are always identical.
3. Individual atoms can be seen with a microscope
4. All atoms of all elements are the same size

Q. Which one of the following pair of compounds illustrates law of multiple proportions?

1. $H_{2}O,N{a}_{2}O$
2. $MgO,N{a}_{2}O$
3. $N{a}_{2}O,BaO$
4. $SnC{l}_2,SnC{l}_4$

Q.

Molality of 40% (by mass of solution) urea solution is??

Q. KF has NaCl structure.What is the distance between K+ and F- in KF if density is 2.48gm cm-3 ?

Q. Law of multiple proportions is not applicable for the oxide(s) of:

1. Carbon
2. Iron
3. Nitrogen
4. Aluminium

Q. What is the molarity and molality of a 13% solution by weight of sulphurics acid with a density of 1.02g/ml. To waht volume should 100ml of this solution be diluted in order to prepare a 1.5N solution?

Please Explain in detail and as simple as you can. Thank you for helping.

Q. Two elements A and B combine to form compounds X and Y. For a fixed mass of A, the masses of B that combine to form the compounds X and Y are in the ratio $3:7$. If in the compound X, $4\text{g}$ of A combines with $12\text{g}$ of B, then in compound Y, $8\text{g}$ of A will combine with _______ $\text{g}$ of B.

1. 24
2. 56
3. 28
4. 8

Q.

Ellingham diagrams normally consists of plots of Δ_fG vs T for the formation of

1. Oxides

2. Sulphide

3. Chloride

4. Nitride

Q.

What is the mass percent of oxygen in ethanol?

1. $52.14\%$

2. $13.13\%$

3. $16\%$

4. $34.73\%$

Q. In a compound A, $1.00\text{g}$ of nitrogen combines with $0.57\text{g}$ of oxygen. In a compound B, $2.00\text{g}$ of nitrogen combines with $2.24\text{g}$ of oxygen. In a compound C, $3.00\text{g}$ of nitrogen combines with $5.11\text{g}$ of oxygen. These data shows which of the following laws?

1. Law of constant proportions
2. Law of multiple proportions
3. Law of reciprocal proportions
4. Dalton’s law of partial pressure

Q.

Explain classical vs statistical thermodynamics.

Q.

33. In an experiment the equilibriurm constant for the
reaction A +B=C+ D is K, when the initial
moles of A and B each is 1.0 moles. Under the
similar conditions in an another experiment if the
initial moles of A and B are taken 2 and 3 moles
then the value of equilibrium constant will be:-

Q. Two different oxides of a metal contain 20% and 27% oxygen by weight. This is in accordance with the law of:

1. Conservation of mass
2. Constant composition
3. Multiple proportions
4. Reciprocal proportions

Q.

The air is a mixture of a number of gases. The major components are oxygen

and nitrogen with approximate proportion of 20% is to 79% by volume at 298

K. The water is in equilibrium with air at a pressure of 10 atm. At 298 Kif the

Henry’s law constants for oxygen and nitrogen are 3.30 × 10⁷ mm and 6.51 × 10⁷ mm respectively, calculate the composition of these gases in water.

Q. Copper oxide was prepared by two different methods. In case one, 1.75 g of the metal gave 2.19 g of the oxide. In the second case, 1.14 g of the metal gave 1.43 g of the oxide. This is explained by which of the following laws?

1. Law of multiple proportions
2. Law of definite proportions
3. Law of partial pressure
4. Gay-Lussac's Law

Q.

Which of the following statements indicates that law of multiple proportion is being followed ?

(a) Sample of carbon dioxide taken from any source will always have carbon and oxygen in the ratio 1 : 2

(b) Carbon forms two oxides namely $C{O}_2$ and CO, where masses of oxygen which combine with fixed mass of carbon are in the simple ratio 2 : 1

(c) When magnesium burns in oxygen, the amount of magnesium taken for the reactoin is equal to the amount of magnesium in magnesium oxide formed

(d) At constant temperature and pressure 200 mL of hydrogen will combine with 100 mL oxygen to produce 200 mL of water vapour

Q. Which one of the following pair of compounds illustrates law of multiple proportions?

1. $H_{2}O,N{a}_{2}O$
2. $MgO,N{a}_{2}O$
3. $N{a}_{2}O,BaO$
4. $SnC{l}_2,SnC{l}_4$

Q. Sulphur and oxygen are known to form two compounds. The sulphur content in one of these is 51% while in the other is 41%. Show that this data is in agreement with the law of multiple proportions.
Hint : Ratio of oxygen in oxides of sulphur is 2 : 3.

Q. 20.An aqueous solution of urea containing 18 g urea in 1500 cc of solution has a density of 1.052 g/cc. If the mol. Wt. Of urea is 60 then the molality of solution is?