NCERT
- Butanone is a four-carbon compound with the functional group (a) carboxylic acid. correct option is c) ketone 2
- Ethane, with the molecular formula C2H6 has (a) 6 covalent bonds. (b) 7 covalent bonds. Correct option is b) 7 covalent bonds. 2
- People use a variety of methods to wash clothes. Usually after adding the soap A soap molecule has two parts namely hydrophobic and hydrophilic. With the help of these, it attaches to the grease or dirt particle and for... 1
- Would you be able to check if water is hard by using a detergent? Detergent gives lather with hard and soft water both, while a soap gives lather with soft water only. Thus, it is not possible to check if w... 1
- What are oxidising agents? Oxidising agents are the substances that gain electrons in redox reaction and whose oxidation number is reduced. 1
- How would you distinguish experimentally between an alcohol and a carboxylic acid? Carboxylic acid on reaction with sodium carbonate produces carbon dioxide gas which turns lime water milky whereas alcohols do not give this... 1
- A mixture of oxygen and ethyne is burnt for welding. Can you tell why a mixture of ethyne and air is not used? 2HC ≡ CH + 5O₂ → 4CO₂ + 2H₂O + Heat When ethyne is burnt in air, it gives a sooty flame. This is due to incomplete combustion caused by limi... 1
- Why is the conversion of ethanol to ethanoic acid an oxidation reaction? CH₃CH₂OH + (Alkaline KMnO₄) → CH₃COOH Since, in this reaction one oxygen is added to ethanol, hence it is an oxidation reaction. 1
- How would you name the following compounds? (i) Bromoethane (ii) Methanal (formaldehyde) (iii) Hexyne 1
- Draw the structures for the following compounds. (i) Ethanoic acid (ii) Bromopentane* (i) Ethanoic acid https://lh3.googleusercontent.com/-ARjQ1Ber6tU/Ya7NyFRf-fI/AAAAAAAAC4Q/5FvOw-OtaigG6V8K3TqXXzZsPPdfp6wgwCNcBGAsYHQ/image.p... 2
- What will be the formula and electron dot structure of cyclopentane? The formula for cyclopentane is C₅H₁₀. Its electron dot structure is given below. 1
- What are the two properties of carbon which lead to the huge number of carbon compounds we see around us? The two features of carbon that give rise to a large number of compounds are as follows: ⇒ Catenation - It is the ability to form bonds with... 1
- How many structural isomers can you draw for pentane? Three structural isomers are possible for pentane. 1
- What would be the electron dot structure of a molecule of sulphur which is made up of eight atoms of sulphur? Sulphur has an atomic number of 16 and an electronic configuration of 2,8,6. The valance electrons on the sulphur atom are six. The sulphur... 1
- What would be the electron dot structure of carbon dioxide which has the formula CO2? Electron-dot structure of carbon dioxide which has the formula CO_(2 ) _() 2
- Give reasons why copper is used to make hot water tanks and not steel (an alloy of iron). Copper does not react with cold water, hot water, or steam. However, iron reacts with steam. If the hot water tanks are made of steel (an al... 2
- A man went door to door posing as a goldsmith. He promised to bring back the glitter of old and dull gold ornaments. The solution he had used was Aqua regia. Aqua regia is Latin word which means ‘Royal Water’. It is the mixture of concentrated Hydrochloric... 1
- Differentiate between metal and non-metal on the basis of their chemical properties Metal Non-metal Metals are electropositive. Non-metals are electronegative. Oxides of metal are basic in nature. Oxides of non-metals are ac... 1
- You must have seen tarnished copper vessels being cleaned with lemon or tamarind juice. Copper reacts with moist carbon dioxide in air to form copper carbonate and as a result, copper vessel loses its shiny brown surface forming... 1
- Carbonate and sulphide ores are usually converted into oxides during the process of extraction. Carbonate and sulphide ores are usually converted into oxides during the process of extraction because metals can be easily extracted from t... 1
- Aluminium is a highly reactive metal, yet it is used to make utensils for cooking. Though aluminium is a highly reactive metal, it is resistant to corrosion. This is because aluminium reacts with oxygen present in air to fo... 1
- Sodium, potassium and lithium are stored under oil. Sodium, potassium, and lithium are very reactive metals and react very vigorously with air as well as water.Therefore, they are kept immerse... 1
- Platinum, gold and silver are used to make jewellery Platinum, gold, and silver are used to make jewellery because they are very lustrous. Also, they are very less reactive and do not corrode e... 1
- What type of oxides are formed when non-metals combine with oxygen? When non-metals are combined with oxygen then neutral or acidic oxides are formed. Examples of acidic oxides are NO₂, SO₂ and examples of ne... 1