CBSE Important Questions

Chemistry Class X

Previous Index
  1. Account for the following
    1. Elements C, N, O and F are all placed in the second period in the periodic table.
    2. Elements of group 17 are monovalent.
    1. How does Atomic Radius change as we more from left to right in a period ?
    2. The positions of three Elements P, Q and R in the Periodic table are shown below

      Which one of the three elements is most non - metallic ?
    1. On dropping a small piece of Sodium into an organic compound “A” with molecular formula C2H6O in a test tube a brisk effervescence is observed.  On bringing a burning splinter the gas evolved burns with a pop sound. Identify ‘A’ and write the chemical equation.
    2. What will happen when you heat the organic compound ‘A’ at 443K with excess of concentrated Sulphuric acid ?
    1. Examine Elements of the third Period : Na, Mg, Al, Si, P, S, Cl, Ar and answer the following :
      Choose
      (i) Metals and
      (ii) Non - Metals out of these elements.
    2. On which side of the Periodic table can we locate
      (i) Metals and
      (ii) Non-Metals?
      Name the Metalloid out of the elements given above. Where are they located in the periodic table ?
  5. Name the functional group present in each of the following compounds.
    C3H7OH
  6. State Modern period law. How many groups and periods are present in modern periodic table ?
    1. List two medicinal use of ethanol.
    2. What happens when ethanol is heated with excess of conc. H2SO4 at 443K (Give chemical equation) ? What role does conc. H2SO4 play in this reaction ?
  8. Give reasons for the following :
    1. Lithium atom is smaller than Sodium atom
    2. Chlorine (Atomic Number 17) is more electronegative than Sulphur (Atomic Number 16)
    1. State modern periodic law.
    2. State the place of metalloids in the periodic table.
  10. Three elements A, B and C have atomic number 7, 8 and 9 respectively.
    1. What would be their positions in the modern periodic table (Mention group and period both)
    2. Arrange A, B and C in the decreasing order of their size.
    3. Which one of the three elements is most reactive and why ?
    1. Draw the electron dot structure of -
      1. C2H2
      2. C2H5OH
    2. What are hydrogenation reactions ? Give an example.
  12. Draw the structure of the simplest ketone.
    1. State Modern Periodic Law.
    2. Why is position assigned to hydrogen in Periodic Table considered anomalous ?
  14. Account for the following :
    1. Elements of group 18 are called zero valent.
    2. Elements in a group of periodic table have similar chemical properties.
    1. Define the term Functional group. Identify the functional group present in the following compounds :
      1. CH3 2CH2 2CH2 2OH
      2. -
    2. What will you observe on adding a 5% alkaline potassium permanganate solution drop by drop to some warm ethanol taken in a test tube ? Write the name of the compound formed during the above chemical reaction.
  16. Given below are four elements with their atomic numbers
    1. Element Atomic number
      A 16
      B 11
      C 3
      D 14
    2. Identify the elements which belong to the same group of the Modern Periodic table.
    3. Arrange the given elements in decreasing order of atomic size.
    4. Write the formula of the oxide of B.
    5. Which of the above elements is a metalloid ?
Submitted By Mr. Atul Kumar Gaur
Email Id : atulgaur@gmail.com
Previous Index