What is difference between an emulsion and a gel?

Emulsion: It is a colloidal mixture in which both the dispersed phase and the dispersion medium are liquids. The two or more liquids present in the mixture are generally immiscible in nature. Example: Milk. Gel: It is a colloid in which the dispersed phase i.e. liquid has combined with the dispersion medium i.e. solid to produce a semisolid material. Example: jellies

Why are medicines more effective in colloidal state?

Medicines are more effective in colloidal state because colloids have a larger surface area. Thus, they get easily assimilated, absorbed and digested. Alternatively, a colloidal state has larger surface area of sol particles and this shows more effective adsorption. Thus, medicines in colloidal state are more effectively absorbed and give better results.

What happens when an emulsion is centrifuged?

When an emulsion is centrifuged, demulsification takes place, i.e. the emulsion is broken into constituent liquids. The lighter water stays towards the centre of the centrifuge and the heavier oil stays on the outside.

What happens when persistent dialysis of a colloidal solution is carried out?

The stability of colloidal solution is due to the presence of a small amount of electrolyte. On persistent dialysis, the electrolyte present is completely removed. As a result, the colloidal solution becomes unstable and gets coagulated.

What happens when a freshly prepared precipitate of Fe ( OH ) 3 is shaken with a small amount of FeCl 3 solution?

When a freshly prepared precipitate of Fe ( OH ) 3 is shaken with a small amount of FeCl 3 solution, a reddish-brown colloidal solution of Fe ( OH ) 3 is obtained. This process is called peptization. The Fe 3 + ions from FeCl 3 are adsorbed on the surface of the precipitate to form a positively charged colloidal solution. FeCl 3 → Fe 3 + + 3 Cl - Fe OH 3 + Fe 3 + → Fe OH 3 Fe 3 + Colloidal solution

How does chemisorption vary with temperature?

Chemisorption increases with temperature up to a certain extent as then after it starts decreasing. Chemisorption occurs due to a chemical reaction between adsorbate and adsorbent, and chemical reactions increase with the increase in temperature.

What is the role of activated charcoal in a gas mask?

Activated charcoal present in gas mask adsorbs the harmful suffocating gases which surround the user and protects them from the particulate matter and ashes present in coal mines. Activated charcoal adsorbs poisonous gases (contaminants) instead of oxygen and provides fresh oxygen for the purpose of inhaling for workers.

CO ( g ) and H 2 ( g ) react to give different products in the presence of different catalysts. Which ability of the catalyst is shown by these reactions?

CO ( g ) and H 2 ( g ) react to give different products in the presence of different catalysts, this shows that the action of a catalyst is highly selective in nature. This selectivity of catalysts is shown in the given reactions: CO ( g ) + H 2 ( g ) → Ni CH 4 ( g ) + H 2 O ( g ) CO ( g ) + 2 H 2 ( g ) → Cr 2 O 3 Cu / ZnO CH 3 OH ( g )

E M B I B E

Chemistry Crash Course (Based on Revised Syllabus-2023)>Chapter -1 - Surface Chemistry>Exercise>Q 37

EASY

12th Goa Board

IMPORTANT

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Cheese is which type of colloid?

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