NARAYANKAR NOTES

2.1 Introduction Summary: • A solution is a homogeneous mixture of two or more pure substances. • It consists of a solvent and one or more solutes. • The particles of a true solution are very small and uniformly mixed. • Solutions are important in daily life, industries and biological processes. --- 2.2 Types of Solutions Summary: • Solutions can be formed from solids, liquids and gases. • Depending on the physical states of solute and solvent, there are nine types of solutions. • Water is the most commonly used solvent. Solid in Liquid Summary: • A solid dissolves in a liquid to form a solution. • Examples: Sugar in water, salt in water. Solid in Solid Summary: • A solid dissolves in another solid. • Examples: Brass, bronze and other alloys. Solid in Gas Summary: • A solid mixes uniformly with a gas. • Example: Iodine vapour in air. Liquid in Liquid Summary: • One liquid dissolves in another liquid. • Examples: Ethanol in water, gasoline. Liquid in Solid Summary: • A liquid dissolves ...

 

  Class 9 Science 1 Chapter 1 Exercise Answers 1. Match the First Column with Appropriate Entries in the Second and Third Columns S. No. Column 1 Column 2 Column 3 1 Negative acceleration The velocity of the object decreases. A vehicle moving with a velocity of 10 m/s stops after 5 seconds. 2 Positive acceleration The velocity of the object increases. A car initially at rest reaches a velocity of 50 km/h in 10 seconds. 3 Zero acceleration The velocity of the object remains constant. A vehicle is moving with a constant velocity of 25 m/s. 2. Clarify the Differences A. Distance and Displacement Distance Displacement Distance is the total length of the actual path travelled by an object. Displacement is the shortest distance between the initial and final positions of an object. Distance is a scalar quantity. Displacement is a vector quantity. Distance has only magnitude. Displacement has both magnitude and direction. ...

  Chapter 1: Solid State – Ultra Quick Revision 1.1 Introduction Strong interparticle forces of attraction . Fixed shape and fixed volume . Very small change with temperature and pressure. Particles may be atoms, ions or molecules . 1.2 Types of Solids Crystalline Solids Regular, repeating arrangement. Long-range order. Sharp melting point. Anisotropic (properties differ with direction). Examples: Ice, NaCl, Diamond, Graphite, Gold, Copper. Amorphous Solids Random arrangement. Short-range order. No sharp melting point. Isotropic (same properties in every direction). Examples: Glass, Plastic, Rubber, Tar. Crystalline vs Amorphous Crystalline Amorphous Regular arrangement Random arrangement Long-range order Short-range order Sharp melting point No sharp melting point Anisotropic Isotropic 1.2.3 Isomorphism, Polymorphism & Allotropy Isomorphism Different substances → Same crystal structure. Same atomi...

  Chapter 1 – Solid State Class 11 Chemistry | Maharashtra State Board 1.1 Introduction In the solid state, the particles are held together by strong interparticle forces of attraction. Because of these strong forces, solids have a definite shape and a definite volume. When temperature or pressure changes, the shape and volume of a solid change only slightly. The smallest particles present in solids may be atoms, ions or molecules. In this chapter, all these smallest particles are called constituent particles or simply particles . Key Points Strong attraction exists between the particles of a solid. Solids have a fixed shape. Solids have a fixed volume. Changes in temperature and pressure produce only small changes in solids. The particles of solids may be atoms, ions or molecules. 1.2 Types of Solids Solids are divided into two main types. Type of Solid Description Crystalline Solid Particles are arranged in ...