(i) Water is added to quicklime - Exothermic (ii) Dilute sulphuric acid is added to zinic granules - Exothermic (iii) Ammonium chloride is dissolved in water in a test tube - Endothermic (iv) The decomposition of vegetable mattel into compost - Exothermic (v) Electrolysis of water - Endothermic (vi)Read more
(i) Water is added to quicklime – Exothermic
(ii) Dilute sulphuric acid is added to zinic granules – Exothermic
(iii) Ammonium chloride is dissolved in water in a test tube – Endothermic
(iv) The decomposition of vegetable mattel into compost – Exothermic
(v) Electrolysis of water – Endothermic
(vi) Silver chloride turns grey in the presence of sunlight to form silver metal – Endothermic.
(a) (i) Lemon juice - 2.0 (ii) Tomato juice - 4.0 (iii) Distilled water - 7.0 (iv) Sodium hydroxide solution - 14.0 (b) Soda water is water containing dissolved carbon dioxide. It is acidic therefore blue litmus solution will turn red.
(a) (i) Lemon juice – 2.0
(ii) Tomato juice – 4.0
(iii) Distilled water – 7.0
(iv) Sodium hydroxide solution – 14.0
(b) Soda water is water containing dissolved carbon dioxide. It is acidic therefore blue litmus solution will turn red.
Food is translocated from leaves to other parts of the plant through phloem. The organic matter, in the form of sucrose, is translocated from mesophyll cells to phloem, using ATP. The increased osmotic pressure causes water from neighbouring cells to move in. This increased pressure moves the sucrosRead more
Food is translocated from leaves to other parts of the plant through phloem. The organic matter, in the form of sucrose, is translocated from mesophyll cells to phloem, using ATP. The increased osmotic pressure causes water from neighbouring cells to move in. This increased pressure moves the sucrose to phloem and to tissues which have less pressure. Once sucrose has been moved out of a cell, using ATP, the water moves back into neighbouring cells. This way phloem is able to send the sucrose according to plants needs.
Classify the following chemical reactions as exothermic or endothermic: (i) Water is added to quicklime. (ii) Dilute sulphuric acid is added to zinc granules. (iii) When ammonium chloride is dissolved in water in a test tube it becomes cold. (iv) The decomposition of vegetable matter into compost. (v) Electrolysis of water. (vi) Silver chloride turns grey in the Presence of sunlight to form silver metal’
(i) Water is added to quicklime - Exothermic (ii) Dilute sulphuric acid is added to zinic granules - Exothermic (iii) Ammonium chloride is dissolved in water in a test tube - Endothermic (iv) The decomposition of vegetable mattel into compost - Exothermic (v) Electrolysis of water - Endothermic (vi)Read more
(i) Water is added to quicklime – Exothermic
See less(ii) Dilute sulphuric acid is added to zinic granules – Exothermic
(iii) Ammonium chloride is dissolved in water in a test tube – Endothermic
(iv) The decomposition of vegetable mattel into compost – Exothermic
(v) Electrolysis of water – Endothermic
(vi) Silver chloride turns grey in the presence of sunlight to form silver metal – Endothermic.
What happens when dilute hydrochloric acid is added to the following? Write balanced chemical equations: (i) Bleaching powder (ii) Zinc granules (iii) Baking soda.
(i) CaOC1₂ + 2HC1 ⟶ Ca1₂ + H₂O +C1₂ (ii) Zn + 2H1 (aq) ⟶ Znc1₂(aq) + H₂(g) (iii) NaHCO₃ (s) + HC1(aq) ⟶ CO₂(g) + H₂O (l)
(i) CaOC1₂ + 2HC1 ⟶ Ca1₂ + H₂O +C1₂
See less(ii) Zn + 2H1 (aq) ⟶ Znc1₂(aq) + H₂(g)
(iii) NaHCO₃ (s) + HC1(aq) ⟶ CO₂(g) + H₂O (l)
Write chemical equations for the reactions taking place when: (i) Iron reacts with steam. (ii) Magnesium (Mg) reacts with dil. HCl. (iii) Copper is heated in air.
(i) Iron reacts with steam 3Fe(s) + 4H₂O (g) ⟶ Fe₃O₄ + 4H₂ (ii) Magnesium reacts with dil. HC1 Mg + 2HC1 ⟶ MgC1₂ + H₂ (iii) Copper is heated in air. 2Cu + O₂ ⟶ 2Cuo
(i) Iron reacts with steam
See less3Fe(s) + 4H₂O (g) ⟶ Fe₃O₄ + 4H₂
(ii) Magnesium reacts with dil. HC1
Mg + 2HC1 ⟶ MgC1₂ + H₂
(iii) Copper is heated in air.
2Cu + O₂ ⟶ 2Cuo
(a) Given below are the pH values of four different liquids: 7.0, 14.0, 4.0, 2.0 Which of these could be that of (i) lemon juice (ii) distilled water (iii) sodium hydroxide solution (iv) tomato juice? (b) When blue litmus solution is added to soda water, what change will be observed and why?
(a) (i) Lemon juice - 2.0 (ii) Tomato juice - 4.0 (iii) Distilled water - 7.0 (iv) Sodium hydroxide solution - 14.0 (b) Soda water is water containing dissolved carbon dioxide. It is acidic therefore blue litmus solution will turn red.
(a) (i) Lemon juice – 2.0
See less(ii) Tomato juice – 4.0
(iii) Distilled water – 7.0
(iv) Sodium hydroxide solution – 14.0
(b) Soda water is water containing dissolved carbon dioxide. It is acidic therefore blue litmus solution will turn red.
How is food translocated from leaves to the other parts of the plant?
Food is translocated from leaves to other parts of the plant through phloem. The organic matter, in the form of sucrose, is translocated from mesophyll cells to phloem, using ATP. The increased osmotic pressure causes water from neighbouring cells to move in. This increased pressure moves the sucrosRead more
Food is translocated from leaves to other parts of the plant through phloem. The organic matter, in the form of sucrose, is translocated from mesophyll cells to phloem, using ATP. The increased osmotic pressure causes water from neighbouring cells to move in. This increased pressure moves the sucrose to phloem and to tissues which have less pressure. Once sucrose has been moved out of a cell, using ATP, the water moves back into neighbouring cells. This way phloem is able to send the sucrose according to plants needs.
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