Haryana State Board HBSE 9th Class Science Notes Chapter 2 Is Matter Around Us Pure Notes.
Haryana Board 9th Class Science Notes Chapter 2 Is Matter Around Us Pure
→ A pure substance is composed of only one type of molecules.
→ Sodium chloride dissolved in water can be separated from water by evaporation or distillation method.
→ Mixture contains more than one substances. .
→ Copper sulphate forms homogeneous mixture in water.
→ The mixture of water and oil is heterogeneous.
→ Lemon water and soda water are examples of solution.
→ In the solution of sugar and water, sugar is solute and water is solvent.
→ Air is a homogeneous mixture of 21% of oxygen and 78% of nitrogen.
→ The molecules of a solution are even smaller than in diameter of 1nm (1 × 10-9m).
→ Solution is a homogeneous mixture from which the molecules of solute cannot be separated by
→ Suspended particles are larger than 100 nm (10-7m). These particles can be seen with eyes.
→ The molecules of colloid spread uniformly in solution.
→ Milk is a colloidal solution.
→ Divergence of sunrays by colloidal molecules is called Tyndall effect.
→ The size of the molecules of colloid is between 1 nm to 100 nm.
→ Different components of colloid can be separated through centrifugation process.
→ Two insoluble liquids can be separated by separating funnel.
→ Ammonium chloride, camphor, naphthalene and anthracene are volatile solid materials.
→ Amixture of two soluble liquids whose components have more difference in their boiling point can be separated through distillation process.
→ The process of crystallization is applied to refine the solid materials.
→ Chemical change brings about change in the chemical properties of matter.
→ On the basis of chemical composition, materials can either be classified into elements or compounds.
→ Elements can generally be divided into metals, non-metals and metalloids.
→ Two elements-mercury and bromine are in liquid state at room temperature.
→ The properties already present in the elements of the compounds are different from that of the properties of the compounds. Though, the elements and compounds present in mixture shows their own properties.
→ Pure Substance: A substance composed of only one type of molecules is called as pure substance.
→ Mixture: A substance composed with the combination of one or more than one pure elements or compounds is called as mixture.
→ Solution: Homogeneous mixture of two or more than two substances is called as solution.
→ Alloys: Those homogeneous mixtures of metals that cannot be isolated through physical processes from their components are called alloys.
→ Solvent: That molecule of solution (whose quantity is more than the other one) which mixes other molecules into solution is called solvent.
→ Solute: That component of solution which dissolved in solvent is called solute.
→ Saturated solution: At a given fixed temperature if in the solution, solute is not miscible, that is called saturated solution.
→ Solubility: That quantity of solute material which at a definite temperature is present in the saturated solution, is called as solubility.
→ Unsaturated Solution: If in any solution quantity of solute material remains little to saturation, then it is called as unsaturated solution.
→ Supersaturated Solution: If in any solution the concentration of Solute is more than that of the saturated concentration, that is called as supersaturated solution.
→ Strength of Solution: Quantity (volume) of solute material dissolved into solvent’s volume is called strength of solution.
→ Suspension: Suspension is an heterogeneous mixture, in which the solute particles do not dissolve rather keep suspending in the medium.
→ Principle of Centrifugation Method: In the centrifugation method, on rotating the mixture fastly the heavier particles settle down at the bottom and the lighter particles come upward.
→ Chromatography: Chromatography is such a process which is used to isolate those solute materials which are dissolved in just one type of solvent.
→ Crystallisation: Crystallisation is that process by which pure solid substance & separated from solution in the form of crystal.
→ Element: Element is that basic form of matter which cannot be further disintegrated into smaller pieces through chemical process.
→ Metalloids: The elements showing the properties in between metals and non-metals are called metalloids, e.g., boron and silicon.
→ Compound: The substance made up of combining chemically two or more than two elements together in the same ratio is called as compound.