Is Matter Around Us Pure - Olympiad Level MCQ, Class 9 Science - Class 9 MCQ

True Solution: True Solution is a homogeneous mixture of two or more substances in which substance dissolved (solute) in solvent has the particle size of less than 10-9 m or 1 nm. Simple solution of sugar in water is an example of true solution.

True solutions example: vinegar

Colloidal:  a homogeneous non-crystalline substance consisting of large molecules or ultramicroscopic particles of one substance dispersed through a second substance. Colloids include gels, sols, and emulsions; the particles do not settle, and cannot be separated out by ordinary filtering or centrifuging like those in a suspension.

Colloids example: Milk

A liquid and a solid together consisting a single phase is known as solution .

Mechanical Properties of Colloidal Particles: Brownian Movement. The dispersed particles present in a colloidal solution exhibit a very important property called Brownian movement. These collisions result in the random zigzag movement of the colloidal particle. The Brownian movement imparts stability to the sol.

Milk: a dispersion of milk fat globules (fat particles) and casein micelles (protein particles) in a continuous phase of water, sugar (lactose), whey proteins, and minerals. Milk Plasma: what is left after you separate the fat globules; equivalent to skim milk for practical purposes.

Light scattering takes place in colloidal solution. Colloid refers to substance which is extremely small and is known for equal dispersion through another material. In colloidal solution any matter is evenly suspended in the liquid.

The types of colloids includes sol, emulsion, foam, and aerosol. Sol is a colloidal suspension with solid particles in a liquid. Foam is formed when many gas particles are trapped in a liquid or solid. Aerosol contains small particles of liquid or solid dispersed in a gas.

Substance which forms colloidal solution in water is starch. 

 

Colloidal solution is a solution in which the colloid mixes uniformly. 

 

All colloids have a Tyndall Effect, which is not exhibited by glucose. 

 

Starch is a colloid and thus when mixed with water can form the colloidal solution. 

 

Thus, the correct option is (C) starch.

Electrophoresis is a process in which particle move under the influence of electric field

Gelatin is made from soft bone and cartilages of an animal which have ability to form thermo- reversible gels and amphoteric character make it as protective colloid.

The process by which the lyophobic sols are protected from coagulation by electrolytes, because of the previous addition of lyophilic colloid is called protection; and the lyophilic colloid employed for imparting this protection, is called protective colloid, Thus when a little gelatin is added to As₂S₃ sol, the latter becomes very stable towards electrolytes and the resulting sol is not coagulated, until a large excess of electrolyte is added. Here, gelatin acts as a protective colloid.

Blue light is scattered in all directions by the tiny molecules of air in Earth's atmosphere. Blue is scattered more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time

A colloid is typically a two phase system consisting of a continuous phase (the dispersion medium) and dispersed phase (the particles or emulsion droplets). The particle size of the dispersed phase typically ranges from 10 to 10000 A^o 

The Tyndall Effect is the effect of light scattering in colloidal dispersion, while showing no light in a true solution. This effect is used to determine whether a mixture is a true solution or a colloid

Brownian motion in colloidal sols arises due to the impact of the molecules of the dispersion medium with the colloidal particles. It has been postulated that the impact of the molecules of dispersion medium on the colloidal particles are unequal. This leads to the zig-zag (random) motion of the colloidal particles.

Unbalanced bombardment of the particles of dispersed phase by molecules of dispersion medium causes Brownian motion. This stabilises the sol.

Difference between Crystalloid and Colloid:
1. Colloids contain much larger molecules than crystalloids do.
 

2. Crystalloid solutions can be stored in room temperature but colloidal solutions cannot be stored in room temperature. They need to be stored in the refrigerator and there is a limited time period for it too.
 

3. The crystalloid solutions can escape the vascular system and distribute throughout the body but colloids cannot. They are restricted to the vascular system.

So, crystalloid particles are smaller, escape through membrane where as colloidal are larger particles and do not escape through membrane.

Charge on blood is negative and that on haemoglobin is positive. It is true. The reason for coagulation to not occur is HEPARIN, a natural anticoagulant that is produced by Basophils and Mast cells in the body.

Ice cream is an emulsion—a combination of two liquids that don't normally mix together. Instead, one of the liquids is dispersed throughout the other. In ice cream, liquid particles of fat—called fat globules—are spread throughout a mixture of water, sugar, and ice, along with air bubbles

 

Hydro means water ,phillic means loving so hydrophilic means water loving colloids

Ultramicroscope, microscope arrangement used to study colloidal-size particles that are too small to be visible in an ordinary light microscope. The particles, usually suspended in a liquid, are illuminated with a strong light beam perpendicular to the optical axis of the microscope.

There are two primary destabilization mechanisms in drinking water treatment: charge neutralization and sweep flocculation. The mechanism is dependent upon the coagulant dose. Most drinking water treatment plants operate using sweep flocculation, which requires a higher coagulant dose, rather than charge neutralization. In charge neutralization, the positively charged metal coagulant is attracted to the negatively charged colloids via electrostatic interaction. Flocs start to form during the neutralization step as particle collisions occur. Adding excess coagulant beyond charge-neutralization results in the formation of metal coagulant precipitates. These metal hydroxide compounds (e.g., Al(OH)3 or Fe(OH)3) are heavy, sticky and larger in particle size. Sweep flocculation occurs when colloidal contaminants are entrained or swept down by the precipitates as they settle in the suspension.

A sol is a colloid made out of very small solid particles in a continuous liquid medium.

The separation of colloidal particles from those of molecular dimensions is called dialysis.
Explanation:
Dialysis is a process used to separate colloidal particles from those of molecular dimensions. It involves the movement of solute molecules through a semipermeable membrane.
Here is a detailed explanation of the process:
1. Colloidal particles are larger in size compared to the molecules present in a solution. They are typically in the range of 1 to 1000 nanometers in diameter.
2. Dialysis utilizes a semipermeable membrane, which allows the passage of smaller molecules (such as water and ions) while restricting the movement of larger particles.
3. A colloidal solution is placed in a dialysis bag or tube made of the semipermeable membrane. The bag is immersed in a solvent (usually water) called the dialyzing medium.
4. Due to the concentration difference between the colloidal solution and the dialyzing medium, there is a net movement of solvent and small molecules out of the colloidal solution and into the dialyzing medium.
5. This process continues until an equilibrium is reached, resulting in the separation of colloidal particles from the solution. The smaller molecules pass through the membrane, while the larger colloidal particles remain inside the bag.
6. Dialysis is commonly used in various fields, including medicine, biotechnology, and chemistry, for the purification and separation of substances.
In conclusion, dialysis is the process of separating colloidal particles from those of molecular dimensions using a semipermeable membrane. It allows for the purification and separation of substances based on their size and molecular weight.

Aerosol contains small particles of liquid or solid dispersed in a gas.

Oxygen is the most abundant element in the Earth's crust. Oxygen makes up 467,100 ppm (parts per million) of the Earth's crust, or 46.6%. It exists as a major compound of the silicate minerals where it combines with other elements. It also exists as a compound in carbonates and phosphates. Oxygen has industrial, medical, and commercial purposes. It is used with acetylene to cut and weld metals. It is used in hospitals to ease respiratory disease and can also be used to manufacture explosives among other numerous uses.

In soda dispersed phase is gas and dispersion medium is liquid. So soda is a example of solution of gas in liquid.

About eight percent of earth crust is aluminium, making it the most abundant metal on this planet. However, it is always find combined with various other elements never by itself in a pure state. Two of them most frequently encountered aluminium compounds are alum and and aluminium oxide.