Double circulation occurs in humans. It refers to the passage of same blood twice through the heart. The right side receives deoxygenated blood whereas the left chambers of the heart pump oxygenated blood. There is no intermixing of oxygenated and deoxygenated blood. The oxygenated blood from lungsRead more
Double circulation occurs in humans. It refers to the passage of same blood twice
through the heart. The right side receives deoxygenated blood whereas the left chambers of the heart pump oxygenated blood. There is no intermixing of oxygenated and deoxygenated blood. The oxygenated blood from lungs comes to left auricle through pulmonary veins. Simultaneously, the deoxygenated blood comes to right auricle through two large veins Contraction of ventricles results in transfer of blood from them into lungs and various body parts. Precisely left ventricle on contraction sends oxygenated blood to body through the largest
artery Aorta. While the right ventricle pumps the blood into lungs and for oxygenation through pulmonary artery. The separation of the right side and left side of the heart is useful so as to prevent oxygenated and deoxygenated blood from mixing. Such separation allows a highly efficient supply of oxygen to the body. This is useful in animals that have high energy needs, such as birds and mammals, Which constantly use the energy to maintain their body temperature.
Relation between oxidation and oxidising agent: Addition of oxygen or removal of hydrogen is called oxidation. The substance that brings about oxidation is called oxidising agent. Example: Fe₂O₃ + 2Al ⟶A1₂O₃ + 2Fe In this example, Fe₂O₃ has acted as oxidising agent and A1 has been oxidised.
Relation between oxidation and oxidising agent:
Addition of oxygen or removal of hydrogen is called oxidation.
The substance that brings about oxidation is called oxidising agent.
Example: Fe₂O₃ + 2Al ⟶A1₂O₃ + 2Fe
In this example, Fe₂O₃ has acted as oxidising agent and A1 has been oxidised.
(i) When Zinc carbonate is calcined : ZnCo₃ ⟶ ZnO + CO₂↑ (ii) When manganese dioxide is heated with aluminum powder: 3MnO₂ + 4A1 ⟶ 3Mn + 2A1₂O₃ (iii) When magnesium is heated with very dil. HNO₃: Mg + 2HNO₃ ⟶ Mg(NO₃)₂ + H₂
(i) When Zinc carbonate is calcined :
ZnCo₃ ⟶ ZnO + CO₂↑
(ii) When manganese dioxide is heated with aluminum powder:
3MnO₂ + 4A1 ⟶ 3Mn + 2A1₂O₃
(iii) When magnesium is heated with very dil. HNO₃:
Mg + 2HNO₃ ⟶ Mg(NO₃)₂ + H₂
(i) Phenolphthalein gives a pink colour with soap because soap contains alkali in traces. (ii) By-products of chlor-alkali Process: NaOH, H ₂ and C1₂ (iii) Universal indicator specifies the various levels of H+ concentration.
(i) Phenolphthalein gives a pink colour with soap because soap contains alkali in traces.
(ii) By-products of chlor-alkali Process:
NaOH, H ₂ and C1₂
(iii) Universal indicator specifies the various levels of H+ concentration.
Quicklime reacts with water to form slaked lime (lime water). It is an exothermic reaction. That is why the container became hot. CaO + 2H₂O ⟶ Ca(OH)₂ + Heat When calcium hydroxide is applied on the wails, it reacts with atmospheric carbon dioxide to form calcium carbonate which gives a shining whitRead more
Quicklime reacts with water to form slaked lime (lime water). It is an exothermic reaction. That is why the container became hot.
CaO + 2H₂O ⟶ Ca(OH)₂ + Heat
When calcium hydroxide is applied on the wails, it reacts with atmospheric carbon dioxide to form calcium carbonate which gives a shining white coating on the walls.
Ca(OH) ₂ + CO₂ ⟶ CaCO₃ + H₂O
Describe double circulation in human beings. why is it necessary?
Double circulation occurs in humans. It refers to the passage of same blood twice through the heart. The right side receives deoxygenated blood whereas the left chambers of the heart pump oxygenated blood. There is no intermixing of oxygenated and deoxygenated blood. The oxygenated blood from lungsRead more
Double circulation occurs in humans. It refers to the passage of same blood twice
See lessthrough the heart. The right side receives deoxygenated blood whereas the left chambers of the heart pump oxygenated blood. There is no intermixing of oxygenated and deoxygenated blood. The oxygenated blood from lungs comes to left auricle through pulmonary veins. Simultaneously, the deoxygenated blood comes to right auricle through two large veins Contraction of ventricles results in transfer of blood from them into lungs and various body parts. Precisely left ventricle on contraction sends oxygenated blood to body through the largest
artery Aorta. While the right ventricle pumps the blood into lungs and for oxygenation through pulmonary artery. The separation of the right side and left side of the heart is useful so as to prevent oxygenated and deoxygenated blood from mixing. Such separation allows a highly efficient supply of oxygen to the body. This is useful in animals that have high energy needs, such as birds and mammals, Which constantly use the energy to maintain their body temperature.
State the relationship between oxidation and oxidising agent in a redox reaction. Give an example of redox reaction showing the relationship between oxidation and oxidising agent.
Relation between oxidation and oxidising agent: Addition of oxygen or removal of hydrogen is called oxidation. The substance that brings about oxidation is called oxidising agent. Example: Fe₂O₃ + 2Al ⟶A1₂O₃ + 2Fe In this example, Fe₂O₃ has acted as oxidising agent and A1 has been oxidised.
Relation between oxidation and oxidising agent:
See lessAddition of oxygen or removal of hydrogen is called oxidation.
The substance that brings about oxidation is called oxidising agent.
Example: Fe₂O₃ + 2Al ⟶A1₂O₃ + 2Fe
In this example, Fe₂O₃ has acted as oxidising agent and A1 has been oxidised.
Write chemical equations for the following reactions: (i) When zinc carbonate is calcined. (ii) When manganese dioxide is heated with aluminium powder. (iii) When magnesium is treated with very dilute nitric acid.
(i) When Zinc carbonate is calcined : ZnCo₃ ⟶ ZnO + CO₂↑ (ii) When manganese dioxide is heated with aluminum powder: 3MnO₂ + 4A1 ⟶ 3Mn + 2A1₂O₃ (iii) When magnesium is heated with very dil. HNO₃: Mg + 2HNO₃ ⟶ Mg(NO₃)₂ + H₂
(i) When Zinc carbonate is calcined :
See lessZnCo₃ ⟶ ZnO + CO₂↑
(ii) When manganese dioxide is heated with aluminum powder:
3MnO₂ + 4A1 ⟶ 3Mn + 2A1₂O₃
(iii) When magnesium is heated with very dil. HNO₃:
Mg + 2HNO₃ ⟶ Mg(NO₃)₂ + H₂
Answer the following questions: (i) State the colour of phenolphthalein in soap solution. (ii) Name the by-product of chlor-alkali process which is used for the manufacture of bleaching powder. (iii) Name one indicator which specifies the various levels of H⁺ ion concentration.
(i) Phenolphthalein gives a pink colour with soap because soap contains alkali in traces. (ii) By-products of chlor-alkali Process: NaOH, H ₂ and C1₂ (iii) Universal indicator specifies the various levels of H+ concentration.
(i) Phenolphthalein gives a pink colour with soap because soap contains alkali in traces.
See less(ii) By-products of chlor-alkali Process:
NaOH, H ₂ and C1₂
(iii) Universal indicator specifies the various levels of H+ concentration.
Rama wanted her house to be whitewashed. She bought some quicklime from the market and dissolved it in water in a big tub. She noticed that the container became hot without any heating. Give reason for her observation with equation and name the product formed. What happens when it is applied on the walls?
Quicklime reacts with water to form slaked lime (lime water). It is an exothermic reaction. That is why the container became hot. CaO + 2H₂O ⟶ Ca(OH)₂ + Heat When calcium hydroxide is applied on the wails, it reacts with atmospheric carbon dioxide to form calcium carbonate which gives a shining whitRead more
Quicklime reacts with water to form slaked lime (lime water). It is an exothermic reaction. That is why the container became hot.
See lessCaO + 2H₂O ⟶ Ca(OH)₂ + Heat
When calcium hydroxide is applied on the wails, it reacts with atmospheric carbon dioxide to form calcium carbonate which gives a shining white coating on the walls.
Ca(OH) ₂ + CO₂ ⟶ CaCO₃ + H₂O