Skip to content

Class X

Property of Sound Waves that Sound needs Material Medium to Travel

The sound waves need material medium to travel because they travel by the vibrations of particles of the medium. The material medium is gas, liquid and solid.  Sound waves are called mechanical waves as they need a material medium for their travel.  An activity described below tells that sound can not travel through vacuum. The …

Property of Sound Waves that Sound needs Material Medium to Travel Read More »

Previous Year’s CBSE Board Questions – Life Processes – Transportation

Transportation What will happen to a plant if its xylem is removed? (Delhi 2009, 1 mark) Need clues – Click here (a) Draw a sectional view of the human heart and level on it – Pulmonary arteries, vena cava, left ventricle.(b) Why is double circulation of blood necessary in human beings? (AI 2009, 5 marks) …

Previous Year’s CBSE Board Questions – Life Processes – Transportation Read More »

Some Important Carbon Compounds -Ethanol and Ethanoic acid

ASSESSMENT – CLICK HERE Previous Year’s CBSE Board Questions -Some Important Carbon Compounds – Ethanol and Ethanoic acid   [googlepdf url=”https://freakgenie.com/wp-content/uploads/2019/02/carbon-compd-ethanol-and-ethanoic-acid.pdf” width=”100%” height=”2560″] ASSESSMENT – CLICK HERE Previous Year’s CBSE Board Questions -Some Important Carbon Compounds – Ethanol and Ethanoic acid

Previous Year’s CBSE Board Questions -Some Important Carbon Compounds – Ethanol and Ethanoic acid

Some Important Carbon Compounds – Ethanol and Ethanoic acid 1. Write the name and molecular formula of an organic compound having its name suffixed with ‘-ol’ and having two carbon atoms in its molecule. Write balanced chemical equation to indicate what happens when it is heated with excess of conc. H2S04 and the name of …

Previous Year’s CBSE Board Questions -Some Important Carbon Compounds – Ethanol and Ethanoic acid Read More »

Common Behaviour of Acids and Bases

In the following section, we will find the answers of  following questions- (i) All acids have similar chemical properties. All bases have similar chemical properties. What   lead to this similarity in properties? (ii) How acids and bases are different chemically?        Group A                                                  Group B ACIDS                                                   BASES                                             Hydrochloric acid (HCl)                      Sodium hydroxide …

Common Behaviour of Acids and Bases Read More »

Importance and Limitations of Modern Periodic Table

Importance of Modern Periodic Table 1. Based on atomic number –     The arrangement of elements in modern periodic table is according to their increasing order of atomic number. Atomic number increases by 1 unit (not fractional) in going from one element to the next element and equal to the number of electrons. Thus, the …

Importance and Limitations of Modern Periodic Table Read More »

Arrangements in Modern Periodic Table    (Long Form of Periodic Table)    

 The arrangement  in periodic table is given by Bohr so it is also known as Bohr’s table or Long form of periodic table. This table is prepared on the basis of – (a) increasing order of atomic number or electronic configuration. (placed in a period) (b) same number of valence electron/electrons. (placed in one group) …

Arrangements in Modern Periodic Table    (Long Form of Periodic Table)     Read More »

INTRODUCTION TO MODERN PERIODIC TABLE

The modern periodic table of elements is based on Mendeleev’s observations. The only difference is instead of being organized by atomic masses, the modern table is arranged by atomic number (Z). Henry Moseley, in 1913, found that atomic number is more fundamental property of an element than its atomic mass. Atomic number helps in arranging …

INTRODUCTION TO MODERN PERIODIC TABLE Read More »

Introduction to Organic Chemistry and Vital Force Theory

     ♦      Earth crust has only 0.02% carbon in the form of minerals (e.g. – carbonates, bicarbonates, coal, petroleum etc.) and atmosphere has 0.03% carbon dioxide. Inspite of its availability in such a small amount, it is highly important for our lives.                                                               ♦     Except water most of …

Introduction to Organic Chemistry and Vital Force Theory Read More »