Question

ly what is the function of digestive enzymes ?
CHEMISTRY
Balance the following chemical equation : Fe(s) + H20 (g) Fe3O4(s) + H2O
@ What is an oxidation reaction ? Give an example of oxidation reaction. Is oxidation an
exothermic or an endothermic reaction ?
What do you mean by precipitation reactions ? Explain by giving examples.
. Translate the following statements into chemical equations and then balance them.
(a) Hydrogen gas combines with nitrogen to form ammonia.
(b) Hydrogen eulphide gas burns in air to five water and sulphur dioxide
(c) Barium chloride reacts with aluminium sulphate to give aluminium chloride and a
precipitate of barium sulphate.
State one reason for the following:
(a) Potato chips manufacturers usually flush bags of chips with nitrogen gas. .
(b) Iron articles lose their shine gradually,
(c) Foods should be kept in airtight containers.
Give reasons for the following:
(a) All decomposition reactions are endothermic reactions.
(b) Colour of copper sulphate solution changes when iron nail is dipped in it.
(c) Respiration is an exothermic reaction.
• Write balanced chemical equations for the following:
(a) Calcium carbonate on reaction with hydrochloric acid gives calcium chloride, wate
and carbon dioxide,
(b) Nitrogen reacts with hydrogen under pressure to form ammonia.​

Answer 1

• digestive enzymes Function  is to digest or to break the complex molecules into simpler substances Ex - trypsin is a digestive enzymes that helps in digestion of proteins.                                                                                                          2)3Fe + 4H2O -----> Fe3O4 + 4H2                                                                                                                                3)   The reaction in which a substance gains oxygen or loses hydrogen is called an oxidation reaction. example-An example of a reaction is that between hydrogen and fluorine gas to form hydrofluoric acid  hydrogen is being oxidized and fluorine is being reduced. The reaction may be better understood if it is written in terms of two half-reactions. Oxidation reactions may be exothermic or endothermic. Eg. All combustion reactions are exothermic and ionisation reaction giving positive ions are endothermic.                                                                        

•  Precipitation reactions are the reactions in which the solid product is formed that settled down at the bottom. Example: bacl2+na2so4 -----> baso4 +2nacl