Maharashtra State Board
- The ratio of corresponding sides of similar triangles is 3:5 then find the ratio of their areas Let the corresponding sides of similar triangle be S1 and S2 , and Areas be A1 and A2 . we know that , S1:S2 =3:5 therefore S₁/S₂=4/5 A₁/A₂=... 1
- Which of the following analytical techniques cannot be used for colourless compounds?
- What is the weight on mars To find out the weights of five friends on the moon and Mars, we need to first understand how the weight of an object changes in different g... 2
- Explain the term earth gravitational force The term "Earth gravitational force" refers to the force that pulls objects towards the Earth. It's the reason things fall when you drop the... 1
- Describe the importance of himalayas Importance of Himalayas: The Himalayas acts as a barrier protecting the great Plains of India from the cold winds of Central Asia during the... 2
- give one example of each elements Hydrogen is an example of element 1
- Give one property common to both hcp and ccp crystal lattices In hcp and ccp crystal lattices coordination number is 12 and packing efficiency is 74%. 1
- Weight of the person on the mars Person on Mars would weigh 37.83% its weight on earth. 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
- A 50% solution of sulphuric acid is subjected to electrolyte oxidation and the product is hydrolysed See below image 2
- CO2 is passed into concentrated solution of NaCl, which is saturated with NH3 . ceunderset(Ammonia)2NH3_((aq))+H2O_((l)) + CO2_((g))->undersetAmmonium carbonate(NH4)2CO3_((aq)) ceundersetAmmonium carbonate(NH4)2CO3_((aq)... 1
- Lithium floats an water while sodium floats and catches fire when put in water. When lithium and sodium react with water, hydrogen gas is released. Due to these hydrogen gas bubbles, lithium and sodium floats on water. e... 2
- BeCl2 is covalent while MgCl2 is ionic. Be²⁺ ion has very small ionic size and therefore, it has very high charge density. Due to this, it has high tendency to distort the electron... 1
- Sodium dissolves in liquid ammonia to form a solution which shows electrical conductivity Sodium dissolves in liquid ammonia giving deep blue coloured solutions which is electrically conducting in nature. Na + (x + y) NH₃ → [Na(NH... 1
- Alkaline earth metals have low values of electronegativity; which decrease down the group Electronegativity represents attractive force exerted by the nucleus on shared electrons.The general outer electronic configuration of alkal... 2
- Standard reduction potential of alkali metals have high negative values. The general outer electronic configuration of alkali metals is ns¹. They readily lose one valence shell electron to achieve stable noble gas... 1