Physical Sciences - Elements, Compounds, and Mixtures

Physical Sciences P2: Question 2

2.1

2.1.1 Definition of Element

An element is a fundamental substance that cannot be broken down into simpler substances through chemical means. Each element is made up of one kind of atom, characterized by a unique number of protons in its nucleus, known as the atomic number. Elements are the basic building blocks of matter and are organized in the periodic table.

2.1.2 Classification of Substance A

Substance A can be classified as an element. Elements consist of only one type of atom, and if Substance A is represented without any additional components or differing atoms that would indicate a compound or mixture, it fits the definition of an element.

2.1.3 Classification of Substance B

Substance B can be classified as either a compound or a mixture, depending on its composition. If it is made up of two or more different types of atoms chemically combined in fixed proportions, it is a compound. If it contains two or more elements or substances that are mixed but not chemically combined, it is a mixture. Since specific details about substance B are not provided, a definitive classification cannot be stated without further context.

2.1.4 Different Atoms in Substance A

Substance A contains one different atom, as it has been classified as an element. An element is composed of only one type of atom, meaning there are no other types of atoms present.

2.1.5 Formula of a Molecule of Substance A

The formula of a molecule of substance A, denoting it as an element, can be represented using an alphabet letter. For example, if we denote substance A as an element represented by the letter X, the molecular formula can simply be written as X. In terms of chemistry, this indicates that it forms the simplest molecular unit of that element, containing only one type of atom.