PRACTICALS First Term 1. To find the pH of the following samples by using pH paper/universal indicator: a. Dilute Hydrochloric Acid b. Dilute NaOH solution c. Dilute Ethanoic Acid solution d. Lemon juice e. Water f. Dilute Sodium Bicarbonate solution 2. To study the properties of acids and bases (HCl & NaOH) by their reaction with: a. Litmus solution (Blue/Red) b. Zinc metal c. Solid sodium carbonate 3. To perform and observe the following reactions and classify them into: i. Combination reaction ii. Decomposition reaction iii. Displacement reaction iv. Double displacement reaction 1) Action of water on quick lime 2) Action of heat on ferrous sulphate crystals 3) Iron nails kept in copper sulphate solution 4) Reaction between sodium sulphate and barium chloride solutions 4. i) To observe the action of Zn, Fe, Cu and Al metals on the following salt solutions: a. ZnSO4 (aq) b. FeSO4 (aq) c. CuSO4 (aq) d. Al2(SO4)3 (aq) ii) Arrange Zn, Fe, Cu and Al (metals) in the decreasing order of reactivity based on the above result. 5. To study the dependence of potential difference (V) across a resistor on the current (I) passing through it and determine its resistance. Also plot a graph between V and I. 6. To determine the equivalent resistance of two resistors when connected in series. 7 To determine the equivalent resistance of two resistors when connected in parallel. 8 To prepare a temporary mount of a leaf peel to show stomata. 9 To show experimentally that light is necessary for photosynthesis. 10 To show experimentally that carbon dioxide is given out during respiration.
TERM I CHAPTER 1- CHEMICAL REACTIONS AND EQUATIONS 1. During chemical reactions, chemical composition of substances changes or new substances are formed. 2.Chemical reactions can be written in chemical equation form which should be always balanced. 3. Types of Chemical Reactions S NO Types of reactions Examples 1 Combination reaction A single product is formed from two or more reactants. 2Mg +O2→2MgO 2 Decomposition reaction A single reactant breaks down to yield two or more products. i) Thermal decomposition 2Pb(NO3)2 → 2PbO + 4NO2 +O2 ii) Electrolysis 2H2O →2H2 +O2 iii) Photo chemical reaction 2AgBr →2Ag +Br2 3 Displacement reaction One element is displaced by another element. Zn + CuSO4→ ZnSO4 + Cu 4 Double displacement reaction Exchange of ions between reactants. AgNO3 +NaCl →AgCl +NaNO3 5 Redox reaction Both oxidation and reduction take place simultaneously CuO + H2 → Cu + H2O 4. i)Exothermic reaction:A chemical reaction in which heat energy is evolved. C + O2 →CO2 (g) + heat ii)Endothermic reaction:A chemical reaction in which heat energy is absorbed. ZnCO3 + Heat →ZnO + CO2 5 .Redox reaction:Chemical reaction in which both oxidation and reduction take place simultaneously.
1.Advantages of VegetativePropagation It allows quicker and easy propagation/exact copy of the parent/ seedless plant propagation. 2 Disadvantages of Vegetative Propagation Vegetative propagation doesn’t favour much variation and evolution of new species. . 3.Regeneration is the ability of an organism to regenerate the lost part.(eg:arm regeneration in star fishes).Sometimes,an organism can be made from its fragmented body parts.e.g. Planaria. 4Flower is the reproductive part of the plant .A complete flower has four whorls-sepals, petals, stamens and carpels. 5 Unisexual flowers and bisexual flowers Unisexual flowers Bisexual flowers Have either stamen or carpel e.g.Water melon, papaya Have both stamen and carpel e.g. hibiscus, rose 6Pollination: Transfer of pollen grains from anther lobe to the stigma of the flower. Pollination Self pollination Cross pollination 7 Post pollination changes in plants
IMPORTANT FORMULAE Relationship between focal length and radius of curvature of a mirror f=R/2 Mirror formula 1/v +1/u =1/f [ V-image distance , U-object distance, f-focal length] Magnification produced by mirror – h’/h = - v/u Snell’s law = = 1n2 Absolute refractive index n = c/v Lens formula 1/v – 1/u = 1/f Magnification produced by lens h’/h = v/u Power of lens P =1/f when focal length is in cm’s P=100/f D RAY DIAGRAMS Fig 10.1 NATURE, IMAGE AND ITS FORMATION (CONCAVE MIRROR) FIG – 10.2 NATURE, IMAGE AND ITS FORMATION (CONVEX MIRROR) Object at infinity Object between infinity and pole Fig- 10.3 NATURE, IMAGE AND ITS FORMATION (CONVEX LENS)
excessive curvature of lens. lens. 2. Hypermetropia Farsightedness Longer focal length of eye lens. Shortening of eye ball. Use of convex lens. 3. Presbyopia Decrease in power of accommodation Ageing, leading to weak ciliary muscles and loss of flexibility of eye lens. Use of eye glasses having bifocal lens. 4. Cataract Milkiness of eye lens Ageing, leading to partial or complete loss of eye sight. Surgery. SOME NATURAL PHENOMENON &CAUSES S.No. Phenomenon Reason 1. Multicolored light coming out of a triangular slab Dispersion of light 2. Rainbow Refraction, dispersion of light and total internal reflection flight in rain drops 3. Twinkling of stars, Advanced sunrise, Delayed sunset ,Flattening of disc of sun at sunrise and sunset Atmospheric refraction of sunlight 4. Blue colour of sky ,Reddening of sun at sun rise and sunset Tyndall effect Scattering of light HUMAN EYE TWINKLING OF STARS FORMATION OF RAINBOWMYOPIA SCATTERING OF LIGHTDISPERSION OF WHITE LIGHT