please do q 15,16,18,19,22 class 7
Answers
16 . (A) CaO
(B) Ca(OH)2
18. Nutrition is the essential organic nutrients living organisms require for growth, maintenance, reproduction and repair. This is an essential process for the organism's survival. Living organisms require energy to survive; this energy is derived from nutrients, or food.
19. the component of gastric juices and their functions are as follows:
HCL hydrochloric acid is the gastric juices that helps in killing germs and harmful bacteria and also it in activating pepsinogen.
pepsinogen is an another gastric juices which when activated produces pepsin.
and pepsin for the breakdown proteins into amino acids.
mucus is another gastric juices that forms the protective layer to prevent corrosion of stomach walls from hydrochloric acid that is concentrated in nature
22. When acetic acid reacts with calcium hydroxide, calcium acetate and water are formed.
2CH3COOH + Ca(OH)2 → Ca (CH3 COO-)2 + 2H2O
(ii) Acids react with bases to form their corresponding salts and water. Ammonia reacts with sulfuric acid to produce ammonium sulfate and water. ... So neutralisation reaction happens and salt will be formed.