Q40.A metal on combustion in excess air forms X . X upon hydrolysis with water yields H2O2 and O2 along with another product. The metal is: (1) Na (2) Mg (3) Li (4) Rb
What This Question Tests
This question tests the ability to calculate water hardness in ppm of CaCO₃ equivalent from the molar concentration of a calcium salt, requiring molar mass and unit conversions.
Concepts Tested
Formulas Used
ppm = (mass of solute in mg / volume of solution in L)
Mass = Moles × Molar Mass
📚 NCERT Sections This Tests
1.25 — Amongst The Following Compounds, Identify Which Are Insoluble, Partially
Chemistry Class 11 · Chapter 1
1.25 Amongst the following compounds, identify which are insoluble, partially soluble and highly soluble in water? (i) phenol (ii) toluene (iii) formic acid (iv) ethylene glycol (v) chloroform (vi) pentanol. 1.26 If the density of some lake water is 1.25g mL–1 and contains 92 g of Na+ ions per kg of water, calculate the molarity of Na+ ions in the lake.
8.17 — Complete Each Synthesis By Giving Missing Starting Material, Reagent Or Products
Chemistry Class 12 · Chapter 8
8.17 Complete each synthesis by giving missing starting material, reagent or products
1.3 — Define The Following Terms:
Chemistry Class 11 · Chapter 1
1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
📋 Question Details
- Chapter
- Hydrogen
- Topic
- Hardness of water
- Year
- 2019
- Shift
- 12 Jan Shift 1
- Q Number
- Q40
- Type
- MCQ
- NCERT Ref
- Class 11 Chemistry Ch 9: Hydrogen
More from this Chapter
Q45.In context with the industrial preparation of hydrogen from water gas (CO + H2), which of the following is the correct statement? (1) CO and H2 are fractionally separated using (2) CO is removed by absorption in aqueous Cu2Cl2 differences in their densities solution (3) H2 is removed through occlusion with Pd (4) CO is oxidised to CO2 with steam in the presence of a catalyst followed by absorption of CO2 in alkali
Q40.Very pure hydrogen (99.9%) can be made by which of the following processes? (1) Reaction of methane with steam (2) Mixing natural hydrocarbons of high molecular weight (3) Electrolysis of water (4) Reaction of salt like hydrides with water
Q37.From the following statements, choose the incorrect statement regarding H2O2 . (1) It has to be kept away from dust. (2) It can act only as an oxidising agent. (3) It decomposes on exposure to light. (4) It has to be stored in plastic or wax-lined glass bottles in the dark.
Q39.Permanent hardness in water cannot be cured by: (1) Treatment with washing soda (2) Ion exchange method (3) Calgon's method (4) Boiling