need five differences between compounds and molecules......
got only one that is ;A molecule is formed when two or more atoms join together chemically. A compound is a molecule that contains at least two different elements.
To find the remaining differences between compounds and molecules, we can approach this by understanding their definitions and properties.
1. Composition: As you rightly mentioned, a molecule is formed when two or more atoms join together chemically. In contrast, a compound is a specific type of molecule that contains at least two different elements. Therefore, all compounds are molecules, but not all molecules are compounds.
2. Types of Elements: Molecules can be made up of either the same type of elements or different types of elements. For example, a molecule of oxygen gas (O2) consists of two oxygen atoms bonded together. This is a molecule made up of the same element. On the other hand, a compound like water (H2O) consists of two hydrogen atoms bonded to one oxygen atom. This is a molecule made up of different elements.
3. Chemical Formula: Molecules are often represented by writing the chemical formula, which indicates the types and number of atoms present in the molecule. For example, O2 represents a molecule of oxygen gas while H2O represents a molecule of water. Compounds also have chemical formulas, but they represent the fixed ratios of different elements within the molecule. For instance, the chemical formula for water (H2O) indicates that there are always two hydrogen atoms and one oxygen atom in every water molecule.
4. Physical Properties: Molecules can exist as gases, liquids, or solids, depending on the nature of the atoms composing them and the strength of their chemical bonds. Compounds also exhibit a variety of physical properties but are often more complex due to the presence of different elements. For instance, water (H2O) is a liquid at room temperature while carbon dioxide (CO2) is a gas. Different compounds can have different melting points, boiling points, colors, and other physical characteristics.
5. Chemical Reactivity: Molecules and compounds can differ in their chemical reactivity. Some molecules may be chemically stable and relatively unreactive, while others can readily participate in chemical reactions. Compounds, being a subset of molecules, often have more specific chemical behavior due to the presence of different elements. This can result in compounds having different chemical reactivities compared to molecules composed of the same elements.
By considering these factors, we can identify the differences between compounds and molecules – composition, types of elements, chemical formulas, physical properties, and chemical reactivity.