Chemistry Reactivity Task 1: Elements and Atoms

When carbon reacts with oxygen it usually forms what compound?

When oxygen reacts with hydrogen it could form what compound?

When iron reacts with oxygen it could form what compound?

What is the usual ending when two elements join in a compound?

What is the ending when three or more elements combine and one of them is oxygen?

If two identical elements combine, what happens to the name?

'Air' is classified as what in terms of its composition?

Which of the following best describes an element?

What are the main components of an atom?

Which of the following is not an element according to the given information?

What is the difference between a compound and an element?

Which of these is a compound?

What is the chemical symbol for sodium?

Which of the following is NOT an element?

What do compounds consist of?

What distinguishes an element from a compound?

Chemical Reactions and Compounds

Carbon typically reacts with oxygen to form carbon dioxide (CO₂).
Oxygen combined with hydrogen usually forms water (H₂O).
Iron reacting with oxygen can produce iron oxide (rust), commonly represented as Fe₂O₃ or FeO.

Naming Conventions in Compounds

Compounds formed from two elements often end in "-ide" (e.g., NaCl is sodium chloride).
Compounds with three or more elements, including oxygen, typically end in "-ate" or "-ite" (e.g., sulfate, nitrate).

Elements and Their Combinations

When two identical elements combine, the name of the element remains the same (e.g., O₂ is oxygen, but named diatomic oxygen).
Air is classified as a mixture due to its composition of various gases, primarily nitrogen and oxygen.

Atomic Structure

An element is defined as a pure substance that cannot be broken down into simpler substances by chemical means.
The main components of an atom are protons, neutrons, and electrons.

Distinction Between Elements and Compounds

A compound consists of two or more elements chemically bonded together, whereas an element consists of only one type of atom.
Examples of compounds include water (H₂O), carbon dioxide (CO₂).

Symbols and Elements

The chemical symbol for sodium is Na.
Not all substances mentioned are elements; for example, compounds like H₂O or CO₂ are not elements as they are composed of multiple types of atoms.

Summary of Key Concepts

Compounds consist of two or more elements in fixed ratios, distinguished from elements which cannot be simplified further.
Understanding the naming conventions and the nature of mixtures versus pure substances is crucial in chemistry.

Test your understanding of elements and atoms in chemistry with this Reactivity Task 1 quiz. Learn about the composition of matter and the basic units that make up everything around us.