Tag: chemistry

Questions Related to chemistry

In the preparation of AgI sol, the excess of $AgNO _{3}$ is added to potassium iodide solution. The particles of the sol will acquire:

chemistry nature of matter heterogenous mixture - colloidal solution and its properties suspensions and colloids mixtures

  1. negative charge

  2. positive charge

  3. no charge

  4. unpredictable

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Correct Option: B

Which statement(s) are correct about colloidal state?

chemistry nature of matter heterogenous mixture - colloidal solution and its properties suspensions and colloids mixtures

  1. The sol particles acquire charge due to preferential adsorption of ions.

  2. Sol particles do not show cataphoresis at isoelectric point.

  3. The stability of protein sol is minimum at its isoelectric point.

  4. The stability of protein sol is due to the presence of charge as well as their extensive solvation nature.

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Correct Option: A,B,C,D
Explanation:
When two or more ions are present in the dispersion medium, then the colloidal particles absorb preferentially positive or negative ions present in the dispersion medium.

Isoelectric point (pI or IEP) is the pH of a solution or dispersion at which the net charge on the molecules or colloidal particles is zero.

Most globular proteins have minimum solubility at or near their isoelectric point.

The stability of the protein solution is normally because of the presence of charge as well as their extensive solvation nature.

So all the statements are correct.

What do you call a mixture where at least two substances are mixed together and stay mixed together?

chemistry nature of matter heterogenous mixture - colloidal solution and its properties suspensions and colloids mixtures

  1. Juice

  2. Colloid

  3. Suspension

  4. None of the answers are correct.

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Correct Option: D
Explanation:

When at least two substances are mixed together and stay mixed together, the mixture is called a homogeneous mixture

The colligative properties of a colloidal solution compared to the solution of non-electrolyte of same concentration will be:

chemistry nature of matter heterogenous mixture - colloidal solution and its properties suspensions and colloids mixtures

  1. same

  2. higher

  3. lower

  4. higher or lower

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Correct Option: C
Explanation:

The colligative properties of a colloidal solution compared to the solution of non-electrolyte of same concentration will be lower as the colloidal solutions are stable due to the presence of charge particle ans also sometimes coagulation happens which reduces the number of particles in the solution and hencem the colligative property.

All colloidal solutions show:

chemistry nature of matter heterogenous mixture - colloidal solution and its properties suspensions and colloids mixtures

  1. very high osmotic pressure.

  2. high osmotic pressure.

  3. low osmotic pressure.

  4. no osmotic pressure.

Show answer
Correct Option: C
Explanation:

All colloidal solutions behave normally as electrolytes and the movement of solvent from solvent to colloidal solution is very less as the concentration gradient for solvent movement is not significant. hence, colloidal solutions show low osmotic pressure.


Hence,option C is correct.

Cloud is an example of foam. This statement is

chemistry nature of matter heterogenous mixture - colloidal solution and its properties suspensions and colloids mixtures

  1. True

  2. False

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Correct Option: B
Explanation:

A cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. They are also known as AEROSOLS. 

Which of the following statements is/are incorrect for diamond?
(a) The refractive index of diamond is highest among solids.
(b) Diamond is hard because all the valence electrons of each carbon atom are involved in bond formation.
(c) Diamond is thermodynamically more stable than graphite.
(d) One carat of diamond represents its weight.

chemistry occurrence of carbon compounds in nature organic compounds allotropes of carbon versatile nature of carbon

  1. All are correct

  2. a, b and c

  3. a and b

  4. c only

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Correct Option: D
Explanation:

Graphite is thermodynamically more stable than diamond, diamond is kinetically stable thus statement c is incorrect. 


Diamonds and other gemstones are weighed in metric carats: one carat is equal to 0.2 grams, about the same weight as a paperclip. Carat is just a unit to represent its weight. 


Diamond also possess an extremely high refractive index and fairly high dispersion. 

Hence, the answer is option $\text{D}$

Carbon in __________ form conducts electricity.

chemistry occurrence of carbon compounds in nature organic compounds allotropes of carbon versatile nature of carbon

  1. diamond

  2. graphite

  3. coal

  4. petroleum

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Correct Option: B
Explanation:

Graphite is an allotrope of carbon. It is an electrical conductor due to vast electron delocalisation within the layers. These are mobile electrons hence responsible for electrical conduction.

The carbon atoms in diamond are bonded to each other by:

chemistry occurrence of carbon compounds in nature organic compounds allotropes of carbon versatile nature of carbon

  1. ionic bond

  2. coordinate bond

  3. hydrogen bonds

  4. covalent bonds

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Correct Option: D
Explanation:

The bonds between carbon atoms in diamond are covalent because covalent bonding is the only option when only nonmetals are present.

The rigid network of carbon atoms, held together by strong covalent bonds, makes diamond very hard. This makes it useful for cutting tools, such as diamond-tipped glass cutters and oil rig drills.

Fullerene, an allotrope of carbon, has 60 carbon atoms joined together and no other element in it. There are various types of fullerenes. $C _{60}, C _{70}, C _{74}$ and $C _{78}$ are the members of the fullerene family. Identify the property due to which such large numbers of carbon atoms are joined together in this molecule :

chemistry allotropy of carbon organic compounds allotropes of carbon versatile nature of carbon

  1. Isomerism

  2. Homologous

  3. Catenation

  4. Metamerism

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Correct Option: C
Explanation:

Catenation is a self-linking property which is maximum present in carbon, because of this property large number of carbon atoms joined together to form molecule.