11th
In this category students supposed to ask questions which belong to std 11th maharashtra board Science
- Find out the difference between Diamond and Graphite Diamond Graphite It has a three-dimensional network structure. It has a two-dimensional hexagonal layered structure. In diamond, each carbon... 1
- Name a molecule having banana bond. Diborane (B₂H₆) 2
- What is hybridization of Al in AlCl3? Al is sp² hybridized in AlCl₃. 2
- Explain the trend of the following in group 13 elements : A. atomic radii B. ionization enthalpy C. electron affinity A. Atomic radii: In group 13, on moving down the group, the atomic radii increases from B to Al. However, there is an anomaly observed in th... 1
- Give the formula of a compound in which carbon exhibit an oxidation state of A. +4 B. +2 C. -4 A. CCl₄ B. CO C. CH₄ 2
- PbCl4 is less stable than PbCl2 i. Pb has electronic configuration [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p². ii. Due to poor shielding of 6s² electrons by inner d and f electrons, it is diff... 1
- Ga3+ salts are better reducing agent while Tl3+ salts are better oxidising agent. i. Both gallium (Ga) and thallium (Tl) belong to group 13. ii. Ga is lighter element compared to thallium Tl. Therefore, its +3 oxidation st... 1
- Identify the group 14 element that best fits each of the following description. i. Carbon (C) ii. Carbon iii. Tin (Sn) and lead (Pb) iv. Carbon 2
- Which of the following shows most prominent inert pair effect ? a. C b. Si c. Ge d. Pb d. Pb shows most prominent inert pair effect 2
- Thallium shows different oxidation state because …………… a. of inert pair effect b. it is inner transition element a. of inert pair effect Thallium shows different oxidation state because of inert pair effect 1
- Haber’s process is used for preparation of …………. a. HNO3 b. NH3 c. NH2CONH2 d. NH4OH b. NH3 Haber’s process is used for preparation of b. NH3 2
- ………… is inorganic graphite. a. borax b. diborane c. boron nitride d. colemanite c. boron nitride is inorganic graphite. 2
- Which of the following is not an allotrope of carbon ? a. buckyball b. diamond c. graphite d. emerald d. emerald is not an allotrope of carbon 2
- Which of the following analytical techniques cannot be used for colourless compounds?
- give one example of each elements Hydrogen is an example of element 1
- Find out the s block elements compounds importance/uses. Important compounds of s-block elements and their uses CompoundUses Sodium chloride, NaCl (common salt)Food seasoning and preservation; raw... 1
- 5. Choose the correct option. A. The unstable isotope of hydrogen is ..... a. H-1 b. H-2 c. H-3 d. H-4 1) The unstable isotope of hydrogen is ….. a. H-1 b. H-2 c. H-3 d. H-4 Answer: c. H-3 2)Identify the odd one. a. Rb b. Ra c. Sr d. Be Answer... 1
- Name the following A. Alkali metal with smallest atom. 1)Alkali metal with smallest atom. Answer: Lithium (Li) 2) The most abundant element in the universe. Answer: Hydrogen (H) 3)Radioactive alk... 1
- Name the isotopes of hydrogen. Write their atomic composition schematically and explain which of these is radioactive ? Hydrogen has three isotopes i.e., hydrogen ( ₁¹ H) , deuterium ( ₁² H) and tritium ( ₁³ H) with mass numbers 1, 2 and 3 respectively. They a... 1
- A water sample, which did not give lather with soap, was found to contain Ca(HCO3 )2 and Mg(HCO3 )2 . Answer: Washing soda ( Na₂CO₃ ) or slaked lime ( Ca(OH)₂ , Clark's method) will make this water give lather. Water containing Ca(HCO₃)₂ and... 1
- Describe the industrial production of dihydrogen from steam. Also write the chemical reaction involved. Answer: Dihydrogen is made industrially by passing steam over hydrocarbons or red-hot coke at high temperature, followed by the water-gas sh... 1
- Describe the diagonal relationship between Li and Mg with the help of two illustrative properties. Answer: Lithium (group 1, period 2) resembles magnesium (group 2, period 3), its diagonal neighbour, because Li⁺ and Mg²⁺ have similar sizes... 1
- Beryllium oxide is treated separately with aqueous HCl and aqueous NaOH solutions. Answer: BeO is amphoteric, so it dissolves in both HCl and NaOH. With aqueous HCl it acts as a base and forms beryllium chloride and water:... 1
- Magnesium is heated in air. Answer: Magnesium burns with a dazzling white light to form magnesium oxide, along with some magnesium nitride. Air is mainly oxygen and nit... 1