plz need answers for these as fast as posibile (easy questions)
Q-1 What happens when: (a) an acid reacts with a base. (b) an acid reacts with a carbonate. ©a drop of acid is dropped on to a blue litmus paper. (d) a few drops of phenolphthalein are added to an alkali. (e) a base is added to red cabbage solution. (f) a non-metallic oxide is dissolved in water. (g) a metallic oxide is dissolved in water. (h) carbon-dioxide is passed through lime-water. Q-2 (i) Vinegar is added in the packaged food items. (ii) In hot climate milk vendors add a small amount of baking soda to milk. (iii) Turmeric stain turns red when soap is applied on it. (iv) Soap solution or baking soda paste is applied on the part of the body stung by a bee. (v)Sodium Chloride is used to make freezing mixtures used by Ice- Cream vendors. (vi)Slaked lime is used in acidic soil. Q-3 Match the following: (1)The gas released when a metal reacts with an acid. Carbon-Dioxide (2)The gas produced when an acid reacts with carbonate. Hydrochloric Acid (3)An acid which is not produced by non-metal oxides. Ammonium Hydroxide (4)An acid used in food industry. Hydrogen (5)A base which is not a metallic oxide or hydroxide. Acetic Acid Q-4 Q-5 All the alkalis are base but all the bases are not alkalis. Explain this statement. Baking powder contains Sodium-Bicarbonate. How does it help in baking a cake.
Due to paucity of time it would not be possible for us to provide the answers to all your queries. We are providing solutions to some your good queries. Try solving rest of the questions yourself and if you face any difficulty then do get back to us.
A-1) (a) When an acid reacts with a base, a salt is formed. This reaction between an acid and a base leading to the formation of a salt is also known as neutralisation reaction. Following is an example
NaOH + HCl → NaCl + H2O
(c) A drop of acid is dropped on a blue litmus paper.
Acid turn blue litmus paper red while bases turn red litmus paper blue. So when a drop of acid is dropped on blue litmus paper, it turns red.
(d) Phenolphthalein is added to an alkali.
Phenolphthalein is an indicators which is colourless in acidic solutions but imparts pink colour to basic solutions. So, when phenolphthalein is added to an alkali, the colour of solution changes to pink.
(h) When CO2 is passed through lime water, it turns milky due to the formation of CaCO3.
Ca(OH)2 + CO2 → CaCO3 + H2O