Tag: chemistry

Questions Related to chemistry

The laws of multiple proportion was proposed by :

chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

  1. Lavoisier

  2. Dalton

  3. Proust

  4. Gay Lussac

Show answer
Correct Option: B
Explanation:

The British scientist, John Dalton proposed the Law of Multiple Proportion.

The % of hydrogen in water and hydrogen peroxide is $11.2$ % and $5.94$ % respectively. This illustrates the law of:

chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

  1. constant proportions

  2. conservation of mass

  3. multiple proportions

  4. law of gaseous volume.

Show answer
Correct Option: C
Explanation:

The law of multiple proportions say that if two elements form more than one compound between them, then the ratios of the masses of the second element which combine with a fixed mass of the first element will be ratios of small whole numbers. 

The oxides of nitrogen contain 63.65%, 46.69% and 30.46% of nitrogen by weight, respectively. This data illustrates the law of:

chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

  1. constant proportions

  2. multiple proportions

  3. reciprocal proportions

  4. conservation of mass

Show answer
Correct Option: B
Explanation:

The law of multiple proportions say that If two elements form more than one compound between them, then the ratios of the masses of the second element which combine with a fixed mass of the first element will be ratios of small whole numbers.
Here, the ratios of oxygen which react with a constant mass of N are $2:3 , 2:1$ and $4:3$ respectively.

The ratio between the different weights of oxygen in different compounds which combine with the same weight of nitrogen ($14$ parts) is $8:16:24:32:40$ or $1:2:3:4:5$.
This is simple whole number which supports the law of:

chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

  1. conservation of mass

  2. multiple proportion

  3. constant composition

  4. reciprocal proportion

Show answer
Correct Option: B
Explanation:

The answer is multiple proportion.
When two elements combine to from two or more than two compounds, the weights of one of the element which combine with a fixed weight of the other, bear a simple whole number ratio is the law of multiple proportion and the given example supports the law.

Different proportions of oxygen in the various oxides of nitrogen proves the law of:

chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

  1. equivalent proportions

  2. conservation of mass

  3. multiple proportions

  4. constant proportions

Show answer
Correct Option: C

0.75 mole of solid ‘$A _4$’ and 2 moles of gaseous $O _2$ are heated in a sealed vessel, completely using up the reactants and producing only one compound. It is found that when the temperature is reduced to the initial temperature, the contents of the vessel exhibit a pressure equal to half the original pressure. What conclusions can be drawn from these data the product of the reaction?

chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

  1. $A _2O _5$

  2. $A _3O _4$

  3. $A _2O _2$

  4. none of these

Show answer
Correct Option: B
Explanation:
give reaction
$A _4(s) + O _2(g) → A _xO _y$

Applying POAC  law for A atoms,
4 × moles of $A _4  =  x \times moles of A _xO _y$
=> $4 \times 0.75 = x \times  1$
=> x = 3

Applying POAC for O atoms,
$2\times  moles of O _2 = y \times moles of A _xO _y$
=> $2 \times 2 = y \times 1$
=> y = 4

Thus, the formula of the product is $A _3O _4$.

The law of multiple proportion was discovered by:

chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

  1. John Dalton

  2. Richter

  3. Joseph Proust

  4. A. Lavoisier

Show answer
Correct Option: A
Explanation:

John Dalton discovered the law of multiple proportion.

Two samples of lead oxide were separately reduced to metallic lead by heating in hydrogen. The percentage weight of lead from one oxide was half the percentage weight of lead obtained from the other oxide. The data illustrates the law of:

chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

  1. reciprocal proportions

  2. constant proportions

  3. multiple proportions

  4. equivalent proportions

Show answer
Correct Option: C
Explanation:

The law of multiple proportions say that If two elements form more than one compounds between them, then the ratios of the masses of the second element which combine with a fixed mass of the first element will be ratios of small whole numbers.

The mass of nitrogen per gram in hydrazine is exactly one and half the mass of nitrogen in the compound ammonia. 


The fact illustrates the:

chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

  1. law of conservation of mass

  2. multiple valency of nitrogen

  3. law of multiple proportion

  4. law of definite proportion

Show answer
Correct Option: C
Explanation:

The law of multiple proportions says that, If two elements form more than one compound between them, then the ratios of the masses of the second element which combine with a fixed mass of the first element will be ratios of small whole numbers.


The ratio of masses of nitrogen per gram of hydrogen in Hydrazine and Ammonia is 1.5:1 = 3:2 Which is simple whole-number ratio.

Therefore, it represents the law of multiple proportions.

Option C is correct.

___________ of elements combine in the ratio of whole numbers to produce a large number of a compound called molecules.

chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

  1. Atom

  2. Ion

  3. Charges

  4. None of the above

Show answer
Correct Option: A
Explanation:

Atoms of elements combine in the ratio of whole numbers to produce a large number of compound called molecules
For example, one $C$ atom combines with one $O$ atom to form one molecule of $CO$. Also, one $C$ atom combines with two $O$ atoms to form one molecule of $CO _2$.