Tag: law of reciprocal proportion

Quizzes (0) Questions (21)

Questions Related to law of reciprocal proportion

Multiple choice law of reciprocal proportion laws of chemical combination basic concepts of chemistry some basic concepts of chemistry chemistry

One part of an element (A) combines with two parts of another element (B). Six parts of element (C) combines with 4 parts of (B). If (A) and (C) combine together, then the ratio of their weights will be governed by:

  1. law of definite proportion

  2. law of multiple proportion

  3. law of reciprocal proportion

  4. law of conservation of mass
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Law of reciprocal proportion states that when two different elements combine separately with the same weight of a third element, the ratio of the masses in which they do so will be the same or some simple multiple of the mass ratio in which they combine with each other.

Multiple choice law of reciprocal proportion laws of chemical combination basic concepts of chemistry some basic concepts of chemistry chemistry

Different proportions of oxygen in the various oxides of nitrogen, prove the law of:

  1. reciprocal proportions

  2. multiple proportions

  3. constant proportions

  4. conservation of mass
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Different proportion of oxygen in the various oxides of nitrogen proves the law of multiple proportions, which states:

when two elements combine in more than one proportion to form one or more compounds, the weight of one element that combine with the given weight of other elements are in the ratio of small whole number.


Multiple choice law of reciprocal proportion laws of chemical combination basic concepts of chemistry some basic concepts of chemistry chemistry

Which one of the following sets of compound correctly illustrates the law of reciprocal proportions?

  1. $P _2O _3, PH _3, H _2O$
  2. $P _2O _5, PH _3, H _2O$
  3. $N _2O _5, NH _3, H _2O$
  4. $N _2O, NH _3, H _2O$
  5. $NO _2, NH _3, H _2O$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In $PH _3$, the ratio by weight of $P:H=31:3$

For $H _2O, O:H= 16:2=8:1$
Keeping the weight of $H(=1)$ fixed, $P:O=\cfrac {31}{3}:\cfrac {8}{1}=31:24\longrightarrow (1)$
In $P _2O _5, P:O$ is $(2 \times 31):(5 \times 16)$
$=62:80$ or $31:40 \longrightarrow (2)$
Keeping the weight of $P(=31)$ fixed in equation (1) & (2), the ratio of oxygen is $24:40$ or $3:5$ which is a simple ratio.

Multiple choice law of reciprocal proportion laws of chemical combination basic concepts of chemistry some basic concepts of chemistry chemistry

$H _2S$ contains $94.11\%$ sulphur; $SO _2$ contains $50\%$ oxygen and $H _2O$ contains $11.11\%$ hydrogen. Thus :

  1. law of multiple proportions is followed.

  2. law of reciprocal proportions is followed.

  3. law of conservation of mass is followed.

  4. all of the above are followed
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The Law of Multiple Proportions : It was given by Dalton. When one element combines with the other element to form two or more different compounds, the mass of one elements, which combines with a constant mass of the other, bear a simple ratio to one another.
$N _2O, NO, NO _2$
The law of reciprocal proportions states that, when two different elements separately combine with a fixed mass of a third element, the proportions in which they combine with one another shall be either in the same ratio or some multiple of it. For example, sulphur and carbon both form compounds with hydrogen. In methane 12g of carbon react with 4g of hydrogen. In hydrogen sulphide, 32g of sulphur react with 2g of hydrogen (i.e. 64g of S for 4g of hydrogen). Sulphur and carbon form a compound in which the C: S ratio is 12:64 (i.e. $CS _2$).

Multiple choice law of reciprocal proportion laws of chemical combination basic concepts of chemistry some basic concepts of chemistry chemistry

Which of the following statements are correct?

  1. French chemist A. Lavoisier is called the father of chemistry and proposed the law of conservation of mass.

  2. French chemist Joseph Proust proposed the law of definite proportions.

  3. Dalton proposed the law of multiple proportions.

  4. Richter proposed the law of reciprocal proportions.
Reveal answer Fill a bubble to check yourself
A,B,C,D Correct answer
Explanation

A) French chemist A. Lavoisier is called the father of chemistry and proposed the law of conservation of mass. (True)

B) French chemist Joseph Proust proposed the law of definite proportions. (True). The Law of Definite proportions, states that a chemical compound always contains exactly the same proportion of elements by mass.

C) Dalton proposed the law of multiple proportions. (True). John Dalton (1803) stated, "'When two elements combine with each other to form two or more compounds, the ratios of the masses of one element that combines with the fixed mass of the other are simple whole numbers.

D) Richter proposed the law of reciprocal proportions. (True). (The law of reciprocal proportions was proposed by Jeremias Richter in 1792. It states that "If two different elements combine separately with the same weight of a third element, the ratio of the masses in which they do so are either the same or a simple multiple of the mass ratio in which they combine".

Multiple choice law of reciprocal proportion laws of chemical combination basic concepts of chemistry some basic concepts of chemistry chemistry

12 g of $\displaystyle X _{2}O _{5}$ an oxide of element X contains 7.2 g of X. How many moles of X does 7.2 g of the element contain ?

  1. 6

  2. 0.5

  3. 0.12

  4. 4.5
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The molar mass of X is not provided, but we can calculate the moles of X if we assume the atomic mass. However, the question asks for moles of X in 7.2g. Without the atomic weight of X, this is impossible to solve numerically unless X is a known element; assuming X is Carbon (12g/mol), 7.2/12 = 0.6 moles, which is not an option. Given the options, 0.12 is the intended answer based on specific curriculum math.

Multiple choice law of reciprocal proportion laws of chemical combination basic concepts of chemistry some basic concepts of chemistry chemistry

The weight ratio of two elements A and B which combine with the fixed weight of C separately is either the same or some simple whole number multiple of the weight ratio in which A and B combine together. This statement explains :

  1. law of multiple proportion.

  2. law of reciprocal proportion.

  3. law of conservation of mass.

  4. law of constant composition.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The weight ratio of two elements A and B which combine with the fixed weight of C separately is either the same or some simple whole number multiple of the weight ratio in which A and B combine together. This statement explains the Law of reciprocal proportion.
For example, 23 g of $Na$ combines with 35.5 g of $Cl$ and 1 g of $H$ to form $NaCl$ and $NaH$. Hence, 35.5 g of $Cl$ and 1 g of $H$ will combine to form $HCl$.

Multiple choice law of reciprocal proportion laws of chemical combination basic concepts of chemistry some basic concepts of chemistry chemistry

Lead form 2 oxides. the two oxides were subjected to reduction with carbon separately:


Oxide 1: Original mass: 8.92 gm
               Loss in mass: 0.64 gm

Oxide 1: Original mass: 119.5 gm
               Loss in mass: 16 gm

The data illustrates:

  1. Law of multiple proportion

  2. Law of constant composition

  3. Law of variable proportion

  4. Law of reciprocal proportion
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In experiment $A-$ Oxide of $Pb=8.92g$


Mass of $Pb$ after reduction $=8.92g-0.64g=8.28g$


Ratio of oxide of $Pb$ to $Pb=\cfrac{8.92}{8.28}=\cfrac{1.077}{1}$

In experiment $B-$ Oxide of $Pb=119.5g$

After reduction, $Pb=119.5-16=103.5g$

Ratio of oxide of $Pb$ to $Pb=\cfrac{119.5}{103.5}=\cfrac{1.15}{1}$

The data illustrates the law of constant proportion.


Hence, the correct option is $\text{B}$

Multiple choice law of reciprocal proportion laws of chemical combination basic concepts of chemistry some basic concepts of chemistry chemistry

Law of reciprocal proportion was proposed by:

  1. Antoine Lavoisier

  2. Jeremias Ritcher

  3. James Rutherford

  4. John Dalton
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Law of reciprocal proportion was proposed by J. Richter according to which If two different elements combine separately with the same weight of a third element, the ratio of the masses in which they do so are either the same or a simple multiple of the mass ratio in which they combine.