Explanation

The ozone layer is a region within the stratosphere, extending from about 15 to 30 km (9 to 19 miles) above the Earth's surface.

It contains a high concentration of ozone (O3), a molecule made up of three oxygen atoms. 

The ozone layer plays a crucial role in protecting the Earth from harmful ultraviolet (UV) radiation from the sun, particularly UV-C and UV-B rays.

Explanation

Amphoteric substances are those that can react with both acids and bases.

They can donate or accept protons (H+ ions), depending on the conditions.

Examples of amphoteric substances include water (H2O), amino acids, and certain metals like zinc and aluminum.

Explanation

Systematic errors are caused by faulty or improper functioning of instruments, or by a flaw in the experimental design.

These errors are consistent and repeatable, and can be identified and corrected.

Explanation

• The general formula for alkanes is CnH2n+2, where n is the number of carbon atoms in the molecule.
• This formula represents the saturated hydrocarbons, also known as paraffins.

Key Points:

• CnH2n is the general formula for alkenes
• CnH2n+1 is the general formula for alcohols

Explanation

Glucose (C6H12O6) is a type of carbohydrate, specifically a simple sugar or monosaccharide.

It is a vital source of energy for many living organisms, including humans.

Glucose is a primary component of many carbohydrates, such as starch, cellulose, and glycogen.

Explanation

Lactose, also known as milk sugar.

It is a disaccharide composed of galactose and glucose molecules.

It is found in milk and other dairy products.

Explanation

The functional group -COOH is the carboxyl group, which is a characteristic functional group of carboxylic acids.

Carboxylic acids are a class of organic compounds that contain this group, examples include:

• Formic acid (HCOOH)
• Acetic acid (CH3COOH)
• Citric acid (C6H8O7)

Explanation

• Organic chemistry is the branch of chemistry that deals with hydrocarbons and their derivatives.
• They are compounds containing carbon and hydrogen atoms.
• It may also contain other elements like oxygen, nitrogen, and sulfur.

Explanation

The stratosphere is the second layer of Earth's atmosphere as you go upwards, lying above the troposphere and below the mesosphere.

The layers of the Earth's atmosphere, in order from the surface, are:

1. Troposphere (up to about 12 km/7.5 miles)
2. Stratosphere (up to about 50 km/31 miles)
3. Mesosphere (up to about 85 km/53 miles)
4. Thermosphere (up to about 600 km/373 miles)

Explanation

Water (H₂O) is a polar solvent due to its asymmetrical molecular structure.

It results in a slightly positive charge on the hydrogen atoms.

A slightly negative charge on the oxygen atom.