Tag: basic concepts of chemistry

Questions Related to basic concepts of chemistry

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 $CO _2$.

Which one of the following pairs of compounds illustrates the law of multiple proportions?

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

  1. $H _{2}O$, $Na _{2}O$

  2. $MgO$, $Na _{2}O$

  3. $Na _{2}O$, $BaO$

  4. $SnCl _{2}$, $SnCl _{4}$

Show answer
Correct Option: D
Explanation:

The law of multiple proportions say that if two elementsform 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. In $SnCl _2$ and $SnCl _4$, the ratio of the weight of Cl reacting with a constant weight of Sn is 2:1.

Atoms of the same two elements can combine in different ratios to form different compounds.
This is:

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

  1. law of constant composition

  2. law of multiple proportion

  3. law of reciprocal proportion

  4. law of conservation of mass

Show answer
Correct Option: B
Explanation:

According to the law of multiple proportion, when two elements combine with each other to form more than one compound, the weights of one element that combines with fixed weight of the other are in the ratio of small whole numbers.

Carbon and oxygen combine to form two oxides, carbon monoxide and carbon dioxide in which the ratio of the weights of carbon and oxygen is respectively 12 : 16 and 12 : 32. These figures illustrate the:

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

  1. Law of multiple proportions

  2. Law of reciprocal proportions

  3. Law of conservation of mass

  4. Law of constant proportions

Show answer
Correct Option: A
Explanation:
When two elements combine to form two or more chemical compounds, then the masses of one of the elements which combined with a fixed mass of the other, bear a simple ratio to one another. For eg, Carbon combines with oxygen to form two compounds namely carbon dioxide and carbon monoxide.

In carbon dioxide, 12 parts by mass of carbon combine with 32 parts by mass of oxygen while in carbon monoxide, 12 parts by mass of carbon combine with 16 parts by mass of oxygen. The masses of oxygen which combined with a fixed mass of carbon in carbon monoxide and carbon dioxide are 16 and 32. These masses of oxygen bear a simple ratio of 16:32 or 1:2 to each other.

Hence, the correct option is $A$.

Law of multiple proportions can be illustrated by taking the example of:

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

  1. $NaOH$ and $KOH$

  2. $NaCl$ and $NaBr$

  3. $SO _2$ and $SO _3$

  4. $H _2CO _3$ and $CO _2$

Show answer
Correct Option: C
Explanation:

Law of multiple proportions, statement that when two elements combine with each other to form more than one compound, the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.

$SO _2$ and $SO _3$ fulfiling this as the weight of oxygen is in ratio of $\dfrac{2}{3}$.

1 g of an oxide of A contained 0.5 g of A, 4 g of another oxide of A contained 1.6 g of A. These figures illustrate 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. reciprocal proportions

  3. multiple proportions

  4. constant proportions

Show answer
Correct Option: C
Explanation:

According to the law of multiple proportion, when two elements combine with each other to form more than one compound, the weights of one element that combines with fixed weight of the other are in the ratio of small whole numbers.

Which of the following sets of compounds follow law of multiple proportions?

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

  1. $NO,\ { NO } _{ 2 }$ and ${ N } _{ 2 }{ O } _{ 5 }$

  2. $CO,\ { CO } _{ 2 }$ and ${ CH } _{ 4 }$

  3. ${ NH } _{ 3 },\ { H } _{ 2 }O$ and ${ NO } _{ 2 }$

  4. ${ H } _{ 2 }O,\ { CO } _{ 2 }$ and ${ CH } _{ 4 }$

Show answer
Correct Option: A
Explanation:

The law of multiple proportions states that when two elements can combine in different ratios to form different compounds, the masses of the element combining with the fixed mass of another element result in the whole-number ratio. 


Hence, for a set of compounds to follow law of multiple proportions, the combining elements must be the same. 

Since the combining element in $NO, NO _2,\ and\ N _2O _5$ are the same, that is Nitrogen and Oxygen. 

Therefore, the correct answer is $A$