Explanation

Preservatives are used to prevent the growth of microorganisms, such as bacteria, yeast, and mold, in food.

They help to extend the shelf life of food products and prevent spoilage.

Preservatives can be found in meats, dairy products, baked goods, and beverages.

Explanation

In an electrochemical cell, reduction occurs at the cathode (positive electrode), where electrons are gained by the oxidized species, causing it to be reduced.

Meanwhile, oxidation occurs at the anode (negative electrode), where electrons are lost by the reduced species, causing it to be oxidized.

Explanation

Water (H₂O) forms strong and extensive hydrogen bonds 

Due to its two hydrogen atoms and two lone pairs on oxygen.

Though HF forms strong individual bonds,

H₂O forms a dense hydrogen bonding network, making its bonding stronger overall.

Explanation

 The charge of cathode ray particles can be determined by passing them through oppositely charged plates. 

Cathode rays are composed of negatively charged particles called electrons.

When these rays pass through an electric field with oppositely charged plates

They are deflected towards the positively charged plate, demonstrating their negative charge. 

Explanation

Proteins and peptides, when hydrolyzed, break down into α-amino acids, which are the building blocks of proteins.

In α-amino acids, the amino group (–NH₂) is attached to the α-carbon, the carbon next to the carboxyl group.

Explanation

Atomicity refers to the number of atoms present in a single molecule of an element or compound.

For example, O₂ has an atomicity of 2, while P₄ has an atomicity of 4.

Explanation

• Transition elements, also known as transition metals, are a group of elements in the d-block of the periodic table.
• They are characterized by their ability to form ions with different charges.
• They are often found in the middle of the periodic table.

Explanation

• The mass number (represented by the letter A) is defined as the total number of protons and neutrons in an atom.
• Consider the table below, which shows data from the first six elements of the periodic table.
• Consider the element helium.
• Its atomic number is 2, so it has two protons in its nucleus.

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

Stoichiometry calculations can only be carried out when all of the above are true:

Irreversible reactions:

Stoichiometry calculations are based on the assumption that the reaction proceeds to completion, meaning all reactants are used up to form products. 

No side reactions:

Side reactions would introduce additional products and complicate the calculations. 

At least one reactant consumed completely:

Stoichiometry calculations determine the amount of products formed based on the amount of a limiting reactant.