Tiêu đề 02. ACIDS BASES and SALTS.pdf ✅

TO DOWNLOAD ORIGINAL VERSION OF PDF CONTACT: +919206306398 PER CLASS PDF COST JUST Rs: 500 Only 02. ACIDS,BASES and SALTS WORKSHEET 1 (1.) Oxygen has an oxidation state of +2 in the compound : (1) H O2 2 (2) CO2 (3) H O2 (4) FO2 (2.) Which of the following is not basic in nature? (1) Saliva (before meal) (2) Toothpaste (3) Saliva (after meal) (4) Tap water (3.) Phenolphthalein is a synthetic indicator and its color in acidic and basic Solutions, respectively are: (1) red and blue (2) blue and red (3) pink and colorless (4) colorless and pink (4.) Magnesium hydroxide is a common base which is used ______ (1) In soap manufacturing (2) As foaming agent in fire extinguishers (3) Antacid to treat stomach acidity (4) To remove grease stains (5.) The difference in number of water molecules in gypsum and plaster of paris is (1) 5 / 2 (2) 2 (3) 1 / 2 (4) 3 / 2 (6.) In the equilibrium – 3 3 2 CH COOH HF CH COOH F + + + (1) F – is the conjugate acid of CH3COOH (2) F – is the conjugate base of HF (3) CH3COOH is the conjugate acid of 3 2 CH COOH+ (4) CH3COOH2 + is the conjugate base of CH3COOH (7.) Ferrous sulphate on heating produces – (1) ferric oxide (2) sulphur dioxide (3) oxygen (4) water (8.) Name of the organic acid present in tomato is : (1) tartaric acid (2) malic acid (3) lactic acid (4) oxalic acid (9.) Which of the following statements is not correct? (1) A chemical equation tells us about the substances involved in a reaction (2) A chemical equation informs us about the symbols and formula of substances involved in a reaction (3) A chemical equation tells us about the atom or molecules of the reactants and products involved in a reaction (4) A chemical equation represents energy changes during a reaction (10.) Which species among the following, can act as an acid and a base is (1) HSO4 − (2) 2 4 SO − (3) H3O + (4) Cl– (11.) Which one of the following types of medicines is used for treatment indigestion– (1) Antibiotic (2) Analgesic (3) Antacid (4) Antiseptic (12.) Which of the following statement is true (1) The conjugate base of a strong acid is a strong base (2) The conjugate base of a weak acid is a strong base
TO DOWNLOAD ORIGINAL VERSION OF PDF CONTACT: +919206306398 PER CLASS PDF COST JUST Rs: 500 Only (3) The conjugate base of a weak acid is a weak base (4) The base and its conjugate acid react to form a neutral solution (13.) Which of the following is weakly acidic? (1) 0.1MHCl (2) 0.1MNaCl (3) 0.1M HC H O 2 3 2 (4) 0.1M CH OH 3 (E) 0.1KOH (14.) According to Bronsted law, water is a/an (1) Base (2) Acid (3) Acid and base both (4) Salt (15.) Baking soda is used as as it is (1) an antacid, a base (2) disinfectant, anti-germs (3) oxidising agent, a bleach (4) a soap, a base (16.) The number of molecules of water of crystallization present in one molecule of ferrous sulfate is (1) 5 (2) 7 (3) 6 (4) 10 (17.) ( )( ) ( ) ( ) ( ) ( ) 2 3 1 4 2 2 3 2 2 2 2 4 5 A A A A Cu H O OH Al H O Cu H O Al H O O H + + + +              + → +     (1) A1 is an acid and A2 is a base (2) A1 is a base and A2 is an acid (3) A3 is conjugate acid of A1 and A4 is conjugate base of A2 (4) A3 is conjugate base of A1 and A4 is conjugate acid of A2 Oxidation number is defined as the charge which an atom of the element has in its ion or appears to have when present in the combined state with other atoms There are certain rules for assigning oxidation number. Some of these rules are given below. • The oxidation number of all the atoms of different elements in their respective elementary states and allotropic forms is taken to be zero. • The O.N. of a monoatomic ion is the same as the charge on it. • The O.N. of hydrogen is +1 when combined with non-metals and is –1 when combined with active metals called metal hydrides • The O.N. of alkali metals (Li, Na, K, etc.) is always 1 and that of alkaline earth metals (Be, Mg, Ca, etc.) is • The algebraic sum of the O.N. of all the atoms in a compound must be zero. In polyatomic ion, the algebraic sum of all the O.N.’s of atoms of the ion must equal the charge on the ion. (18.) What is the correct increasing order of oxidation state of nitrogen in following compounds : NH , N , NH OH, NO 3 2 2 2 (1) NH NO N NH OH 3 2 2 2    (2) NO NH NH OH NH 2 3 2 3    (3) NH NH OH NO N 3 2 2 2    (4) NH NH OH N NO 3 2 2 2    (19.) Hydrogen sulphide ( H S2 ) is a strong reducing agent. Which of the following reactions shows its reducing action – (1) Cd(NO ) H S CdS 2HNO 3 2 2 3 + → + (2) CuSO H S CuS H SO 4 2 2 4 + → + (3) 3 2 2 2FeC1 H S 2FeC1 2HC1 S + → + + (4) Pb(NO ) H S PbS 2CH COOH 3 2 2 3 + → + (20.) Baking soda is not used: (1) in baking. (2) as an ingredient in antacids. (3) in fire- extinguishers. (4) as a disinfectant.
TO DOWNLOAD ORIGINAL VERSION OF PDF CONTACT: +919206306398 PER CLASS PDF COST JUST Rs: 500 Only WORKSHEET 2 (21.) Plaster of Paris is a hemihydrate of ______. Complete the statement. (1) Calcium carbonate (2) Calcium sulphate (3) Sodium hydrogen carbonate (4) Sodium chloride (22.) When the gases sulphur dioxide and hydrogen sulphide mix in the presence of water, the reaction is SO 2H S 2H O 3S 2 2 2 + → + . Here hydrogen sulphide is acting as – (1) an oxidising agent (2) a reducing agent (3) a dehydrating agent (4) a catalyst (23.) During the preparation of hydrogen chloride gas on a humid day, the gas is usually passed through the guard tube containing calcium chloride. The role of calcium chloride taken in the guard tube is to (1) absorb the evolved gas (2) moisten the gas (3) absorb moisture from the gas (4) absorb Cl– ions from the evolved gas (24.) Match the following columns: Column (I) Column (II) (1) Bleaching powder (a) Sodium bicarbonate (2) Baking soda (b) Sodium carbonate (3) Washing soda (c) Calcium oxychloride (4) Plaster of Paris (d) Calcium sulphate hemihydrate (1) (1 c , 2 a , 3 b , 4 d ) → → → → ( ) ( ) ( ) ( ) ( ) ( ) ( ) (2) (1 , 2 , 3 , 4 ) → → → → (a b c d ) ( ) ( ) ( ) ( ) ( ) ( ) (3) (1 , 2 , 3 , 4 ) → → → → (b c d a ) ( ) ( ) ( ) ( ) ( ) ( ) (4) (1 , 2 , 3 , 4 ) → → → → (d a b c ) ( ) ( ) ( ) ( ) ( ) ( ) (25.) ( ) ( ) ( ) ( ) 3 3 AgNO aq NaCl aq AgCl s NaNO aq + → + Above reaction is – (1) precipitation reaction (2) double displacement reaction (3) combination reaction (4) redox reaction An element placed above in the activity series will replace the element placed below it from its aqueous solution. Reactivity of metals towards other elements decreases as you go down the series. The stability of their compounds also decreases. Any metal above hydrogen reacts with acids, replacing hydrogen. The more active a metal, the more strongly it holds onto oxygen in an oxide and therefore, the more strongly the oxide resists decomposition into its elements upon heating. The most active metals are not likely to remain uncombined with other substances for very long. Some are so active that they must be isolated from air when they are stored. (26.) Copper displaces which of the following metals from its salt solution (1) 4 ZnSO (2) FeSO4 (3) AgNO3 (4) NiSO4 (27.) Which of the following is used for dissolution of gold? (1) Hydrochloric acid (2) Sulphuric acid (3) Nitric acid (4) Aqua regia (28.) What is/are formed when acids react with carbonates? (1) Salt (2) Water (3) Carbon dioxide (4) All of above
TO DOWNLOAD ORIGINAL VERSION OF PDF CONTACT: +919206306398 PER CLASS PDF COST JUST Rs: 500 Only (29.) If a few drops of a concentrated acid accidentally spills over the hand of a student, what should be done? (1) Wash the hand with saline solution (2) Wash the hand immediately with plenty of water and apply a paste of sodiumhydrogencarbonate (3) After washing with plenty of water apply solution of sodium hydroxide on the hand (4) Neutralise the acid with a strong alkali (30.) Which of the following is a conjugated acid base pair? (1) HCl, NaOH (2) NH4Cl, NH4OH (3) H2SO4, HSO4 − (4) KCN, HCN (31.) C2H5ONa is a..... in C2H5OH (1) Strong base (2) Strong acid (3) Weak acid (4) Weak base (32.) Ammonia gas is formed by the combination of nitrogen and hydrogen 2 2 3 N H NH 3 2 + → In the above equation (1) nitrogen and hydrogen are reactants (2) one molecule of nitrogen combine with 3 molecule of hydrogen and forms two molecule of ammonia (3) one volume of nitrogen and three volume of hydrogen combine and give 2 volume of ammonia gas (4) reactants and products are not gaseous. (33.) When hydrogen sulphide gas is passed through a blue solution of copper sulphate, a black precipitate of copper sulphide is obtained and the sulphuric acid so formed remains in the solution. The reaction is an example of – (1) a combination reaction (2) a displacement reaction (3) a decomposition reaction (4) a double decomposition reaction (34.) Equal volumes of hydrochloric acid and sodium hydroxide solutions of same concentration are mixed and the pH of the resulting solution is checked with a pH paper. What would be the colour obtained? (1) Red (2) Yellow (3) Yellowish green (4) Blue (35.) Take about 1.0g CaCO3 in a test tube. Heat it over a flame, when a colourless gas comes out. The reaction is called a (1) decomposition reaction (2) displacement reaction (3) double decomposition reaction (4) double displacement reaction (36.) A bottle of fire extinguishers contain H SO 2 4 and (1) CaCO3 (2) MgCO3 (3) NaHCO3 (4) Any carbonate (37.) Which of the given indicators will show no change in basic medium? (1) Turmeric paper (2) Red litmus (3) Phenolphthalein (4) Methyl orange (38.) Non-metals + acids → (1) slow reaction (2) violent reaction (3) moderate reaction (4) no reaction (39.) Which of the following statements is true for acids? (1) Bitter and change red litmus to blue (2) Sour and change red litmus to blue (3) Sour and change blue litmus to red (4) Bitter and change blue litmus to red (40.) Which of the following acids will not have a corrosive or painful action on skin? (1) Concentrated nitric acid (2) Concentrated hydrochloric acid