Maharashtra State Board Class 7 Science Elements Compounds and Mixtures Notes / Textbook Exercises and Extra Question and Answers.
Class 7 Science Elements Compounds and Mixtures Notes
Matter:
- Matter refers to the substance an object is made of.
- It can exist in solid, liquid, or gaseous states.
- An object’s properties are determined by the matter it contains.
Properties of Matter:
- Matter has two essential properties: mass and volume.
- Mass and volume are attributed to the substances that matter comprises.
Substances:
- Substances are forms of matter made of a single constituent.
- Examples include gold, diamond, water, and chalk.
- These substances have consistent properties.
Mixtures:
- Mixtures are combinations of two or more substances.
- Proportions of components in mixtures can vary.
- No chemical change occurs during mixture formation.
Particles of Matter:
- All matter consists of tiny particles.
- The smallest particles are molecules.
- Elements are substances composed of identical atoms and cannot be further decomposed.
Elements:
- Elements are represented by symbols derived from their names.
- Some elements share initial letters, leading to the use of pairs of letters for symbols.
- Elements are classified into metals, non-metals, and metalloids based on their properties.
Compounds:
- Compounds are formed by the chemical combination of atoms from different elements.
- Compounds have properties distinct from their constituent elements.
- They are represented by molecular formulas.
Separating Mixtures:
Unwanted substances in mixtures can be separated using methods such as filtration, sorting, winnowing, and sublimation.
