Explanation

 Chromatography involves the distribution of mixture components between a mobile phase and a stationary phase.

The mobile phase is a fluid stream (liquid or gas) that carries the components of the mixture

While the stationary phase is a fixed material that interacts with these components

Slowing their movement and leading to separation

Explanation

Repeated extraction using portions of solvent is more efficient than using a single large portion of solvent. 

Efficiency in repeated extractions:

When you use small portions of solvent repeatedly, each extraction removes a portion of the solute from the original solution, maintaining a higher concentration gradient for subsequent extractions.

This leads to a more efficient transfer of the solute to the solvent.

Concentration gradient:

By repeatedly adding fresh solvent, you create a higher concentration difference between the solute in the original solution and the solvent, allowing for better transfer of the solute.

Single extraction limitation:

Using a single large volume of solvent may not be as efficient because the solute may not have enough time to fully transfer to the solvent due to a lower concentration gradient. 

Explanation

Filtration by a glass funnel and filter paper is very time-consuming.

Filtration using traditional tools like a glass funnel and filter paper is a slow process because:

Liquid passes through the filter gradually

Solids take time to separate completely

So, it takes a lot of time, which is what "time-consuming" means.

Explanation

The ratio of hydrogen to oxygen by mass in water is always 1:8. 

This ratio is derived from the atomic masses of hydrogen (approximately 1 g/mol) and oxygen (approximately 16 g/mol) in the water molecule (H₂O),

Where there are two hydrogen atoms and one oxygen atom.

Therefore, the mass ratio is (2 * 1) : 16, which simplifies to 2:16 or 1:8. 

Explanation

Sulfur is used in insecticides to control pests and fungi.

It is also used in treating skin diseases like scabies and acne, and in making fireworks due to its flammability.

Explanation

The chemical formula of quick lime (commonly referred to as lime) is Calcium Oxide (CaO).

It is used in construction, steelmaking, and as a chemical reagent.

Explanation

Air is a mix of gases, with nitrogen (78%) and oxygen (21%) being the main components.

The plus trace amounts of other gases like argon, carbon dioxide, and water vapor.

Explanation

Cooking gas, also known as liquified petroleum gas (LPG), is a mixture of propane and butane.

It is a flammable mixture of hydrocarbon gases.

Explanation

 Grignard reagent (RMgX) reacts with aldehydes (other than formaldehyde) to form secondary alcohols after acid hydrolysis.  

- With formaldehyde, it gives primary alcohol.  

- With ketones, it gives tertiary alcohol.

Explanation

 Pb₃O₄ is commonly known as red lead, and its chemical name is lead tetraoxide, as it contains both Pb(II) and Pb(IV) oxidation states.