Question 1

Which subatomic particle determines the identity of an element, and how is this reflected in the periodic table?

Accepted Answer

Proton; the number of protons (atomic number) determines the element's identity.

Question 2

Referencing the first image, which part of the atom is responsible for most of its mass?

Accepted Answer

Nucleus

Question 3

What is the main difference between ionic and covalent bonds as illustrated in the images?

Accepted Answer

Ionic bonds involve transferring electrons, while covalent bonds involve sharing electrons.

Question 4

Given the chemical reaction $$2H_2 + O_2$ \rightarrow 2H_2O$$, what type of bond is formed between hydrogen and oxygen in water?

Accepted Answer

Covalent bond

Question 5

Why is water considered a polar molecule, as shown in the images?

Accepted Answer

Because oxygen attracts shared electrons more strongly, creating partial charges.

Question 6

Which property of water allows it to dissolve salts, as depicted in the images?

Accepted Answer

Its ability to form hydrogen bonds with ions

Question 7

What is the structural difference between saturated and unsaturated fatty acids, as shown in the lipid images?

Accepted Answer

Unsaturated fatty acids have double bonds causing kinks in the chain.

Question 8

Which type of lipid is the main component of cell membranes?

Accepted Answer

Phospholipids

Question 9

What is the role of dehydration synthesis in the formation of polymers, as shown in the images?

Accepted Answer

It joins monomers by removing a water molecule.

Question 10

Which carbohydrate is used for energy storage in animal cells, as shown in the polysaccharide image?

Accepted Answer

Glycogen

Question 11

What is the monomer of proteins, as illustrated in the amino acid images?

Accepted Answer

Amino acid

Question 12

Which bond joins amino acids together in a protein, as shown in the peptide bond image?

Accepted Answer

Peptide bond

Question 13

What determines the primary structure of a protein?

Accepted Answer

The sequence of amino acids in the polypeptide chain

Question 14

Which interaction is NOT involved in maintaining the tertiary structure of a protein?

Accepted Answer

Peptide bonds

Question 15

What is the main function of nucleic acids in cells?

Accepted Answer

Storing and transmitting genetic information

Question 16

Which molecule is the universal energy currency of the cell?

Accepted Answer

ATP

Question 17

What happens to ATP when it is used for energy in the cell?

Accepted Answer

It is broken down into ADP and a phosphate group.

Question 18

Which property of water is most important for maintaining stable temperatures in cells?

Accepted Answer

Its high heat capacity

Question 19

What is the effect of adding an acid to water, according to the pH scale?

Accepted Answer

It increases the concentration of H+ ions, lowering the pH.

Question 20

How do buffers help maintain pH in cells?

Accepted Answer

By combining with H+ ions or releasing H+ ions to stabilize pH

Chapter 2: Chemical Principles – Atoms, Molecules, and the Chemistry of Life

Study Guide - Practice Questions