The pure solids or crystalline solids melt sharply. The temperature remains constant at its melting point until all the solid melts. There are some solids which pass through turbid state before melting. These turbid phases are called liquids crystals because they can flow as liquids. […]
Whenever matter undergoes a physical or’ a chemical change, it is always accompanied by an energy change in the form of heat. This change in energy is the quantitative measure of the difference in the strength of intermolecular forces. In case of physical change at […]
The pressure above the surface of the liquid by the vapours at equilibrium between liquid and its vapours at a particular temperature is called equilibrium vapour pressure or simply vapour pressure. Explanation: If we enclosed a liquid in a vessel, molecules start to evaporate above […]
The lower density of ice than liquid water at 0°C compels water in ponds and lakes to freeze from surface to the downward direction. Water attains the temperature of 4°C by the fall of temperature in the surrounding. As the outer atmosphere becomes further cold, […]
When the temperature of water is decreased and ice is formed then the molecules become more regular and this regularity extends throughout the whole structure. Empty spaces are left behind as shown in the figure below. That is why when water freezes it occupy 9% […]
Soaps and detergents perform the cleaning action because the polar parts of their molecules are water soluble due to hydrogen-bonding and non-polar parts remain outside water.