English

Give a Reason for the Following Statement: Components in a Mixture Are Present in Varying Proportions and Not in a Fixed Proportion.

Advertisements
Advertisements

Question

Give a reason for the following statement:

Components in a mixture are present in varying proportions and not in a fixed proportion.

Short/Brief Note
Advertisements

Solution

A mixture is an impure substance containing more than one element or compound, mechanically mixed together in any proportion and the mixture retains the properties of its constituents i.e. elements or compounds.

shaalaa.com
  Is there an error in this question or solution?
Chapter 3: Elements, Compounds and Mixtures - Objective Type Questions

APPEARS IN

Viraf J. Dalal Simplified Middle School Chemistry [English] Class 7 ICSE
Chapter 3 Elements, Compounds and Mixtures
Objective Type Questions | Q 4.3

RELATED QUESTIONS

Name: a Liquid Non-metal


Give two examples of the following.
Metals which are soft


Define: Atom 


Name: Two substances used to make electric wires


Fill in the blank
A metal which is a liquid at room temperature is _______.


Indicate whether the following statement is true or false:
Molecules can exist independently.


Tick (√) the correct alternative from the choice given for the following statement

A non-metal which is a good conductor of electricity.


Elements are classified into – Metals – Non-metals – Metalloids – Noble gases. State which of A, B, C, D is a –

1. Metallic element
2. Non-metallic element
3. Metalloid
4. Noble gas.

A: Is non-malleable, non-ductile & a poor conductor of electricity ___________
B: Has lustre, is malleable and ductile & a good conductor of heat ___________
C: Is unreactive and inert and present in traces in the air _________
D: Shows properties of both metals and non-metals ___________


Give the name of the radical - OH


Write the names of elements from the following symbol:

Cd


Write the names of elements from the following symbol:

Ti


Write the names of elements from the following symbol:

Cu


Select the correct answer to the statement given below:

The chemical name for dinitrogen oxide [N20].


Define the terms elements, compounds & mixtures with a view to show their basic difference.


Match the separation of components in List I with the most appropriate process in List II.

List I List II
1. Naphthalene from naphthalene & sodium chloride. A: Separating funnel
2. Cream from milk. B: Sublimation
3. Kerosene oil from kerosene oil & water. C: Boiling 
4. Lead nitrate from an aqueous solution of lead nitrate. D: Centrifugation
5. Ammonia from an aqueous solution of ammonia. E: Distillation

The diagram represents fractional distillation for the separation of mixtures. Answer the following :

  1. Can two immiscible liquids be separated by this process?
  2. Separation of liquids by this process is based on which physical property?
  3. If methyl alcohol & water are to be separated, which liquid would remain in flask ‘X’ after condensation.
  4. Give a reason for the above answer.
  5. State the purpose of the fractionating column in the apparatus.

Elements are made up of______ kinds of atoms.


Name the constituents of water.


Give an account of elements known to us.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×