Tag: basic concepts of chemistry

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

100 ml of hydrogen combine with 50 ml of oxygen to give 100 ml of water vapour. This statement is according to:

  1. Law of multiple proportions

  2. Gay Lussac's law

  3. Avagadro's law

  4. Dalton's atomic theory
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Law of multiple proportions states that, when two elements combine to form more than one compound, the weights of the combining elements are in a ratio of small whole numbers.


Here, the hydrogen and oxygen combine in a ratio of $2:1$


So it is according to the law of multiple proportions and the correct answer is ( A )

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

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

  1. $H _2O, Na _2O$
  2. $MgO, Na _2O$
  3. $Na _2O, BaO$
  4. $SnCl _2, SnCl _4$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Law of Multiple Proportions - 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.  

The elements, tin and chlorine combines in different proportions to form the compounds.

Hence SnCl$ _2$ and SnCl$ _4$ illustrates the law of multiple proportions.  

Hence, the correct option is $\text{D}$
Multiple choice chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

An elements forms two oxides containing respectively 53.33 and 36.36 percent of oxygen. These figures illustrate the law of :

  1. Conservation of mass

  2. Constant proportions

  3. Reciprocal proportions

  4. Multiple proportions
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

An element forms to oxides containing different percentages of oxygen this illustrates that a fixed mass of the elements combine to give more than one compound then they would do so in a simple whole number ratio. Hence this illustrates law of multiple proportions.

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

Among the following pairs,the one which illustrates the law of multiple proportions is_____.

  1. $NH _3, \ HCl$
  2. ${ H } _{ 2 }S,{ SO } _{ 2 }$
  3. $CuO,{ Cu } _{ 2 }O$
  4. ${ CS } _{ 2 },{ FeSO } _{ 4 }$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The law of multiple proportions applies to pairs of compounds formed by the same two elements. CuO and Cu2O are both formed by copper and oxygen, making them the correct pair.

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

A hybrid rocket propellant uses:

  1. a liquid oxidizer and a solid fuel

  2. a complete solid propellent

  3. a beleqiud propellent

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Hybrid propellant engines represent an intermediate group between solid and liquid propellant engines. One of the substances is solid, usually the fuel, while the other, usually the oxidizer, is liquid. 

The liquid is injected into the solid, whose fuel reservoir also serves as the combustion chamber. The main advantage of such engines is that they have high performance, similar to that of solid propellants, but the combustion can be moderated, stopped, or even restarted. It is difficult to make use of this concept for vary large thrusts, and thus, hybrid propellant engines are rarely built.

A hybrid engine burning nitrous oxide as the liquid oxidizer and HTPB rubber as the solid fuel powered the vehicle SpaceShipOne, which won the Ansari X-Prize.

Hence, the correct option is $\text{A}$
Multiple choice chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

Which of the following pairs of compound illustrate law of multiple proportions ?

  1. KOH, CsOH
  2. $ H _2O, D _2O $

  3. Ethane , benzene

  4. KCI, KBr
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ethane (C2H6) and benzene (C6H6) are both hydrocarbons (composed of carbon and hydrogen). While they are not the most standard example, they illustrate the law of multiple proportions as they are different compounds formed by the same two elements.

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

$i$. Percentage of $Mg$ in $MgO$ and $MgCl _{2}$ 

$ii$. Percentage of $C$ in $CO$ and $CO _{2}$
$iii$. Percentage of $Cr$ in $K _{2} Cr _{2}O _{7}$ and $K _{2}CrO _{4}$ 
$iv$. Percentage of $Cu$ isotopes in $Cu$ metal
The law of multiple proportions may be illustrated by data given by:

  1. $ii$
  2. $iv$
  3. $i$ and $ii $
  4. $i,\ ii$ and $iii$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

According to law of multiple proportion, if two elements combine to form more than one compound, then the weight of one element combining with the fixed weight of other, in the two compounds, is in a whole number ratio.

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

Law of multiple proportions is not applicable for the oxides (s) of __________.

  1. carbon

  2. iron

  3. nitrogen

  4. aluminium
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Law of multiple proportions

If two elements chemically combine to give two or more compounds, then the weight of one element which combines with the fixed weight of the other element in those compound bear a simple multiple ratios to one another.

Eg: Nitrogen forms the oxides- $N _2O, NO, N _2O _3, NO _2, N _2O _5$

But aluminium form only 1 type of oxide $Al _2O _3$.
Multiple choice chemistry basic concepts of chemistry law of multiple proportion law of multiple proportions laws of chemical combination

The oxides of a certain (hypothetical) element contain 27.28 %, 42.86% and 52.94% oxygen. What is the ratio of the valances of the element in the 3 oxides? 

  1. 2 : 3 : 4

  2. 1 : 3 : 4

  3. 1 : 2 : 4

  4. 1 : 2 : 3
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The oxygen percentages are 27.28%, 42.86%, and 52.94%. Assuming 100g of oxide, the mass of the element is 72.72g, 57.14g, and 47.06g. The ratio of oxygen to element mass (normalized) leads to valency ratios of 1:2:3.

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

$CO,CO _2, C _2O _3$ follows :

  1. law of definite proportion

  2. law of multiple proportion

  3. law of conservation of mass

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

The Law of Multiple Proportion: 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.
So, $CO,CO _2, C _2O _3$ follows law of multiple proportion.