CognitoQuiz

Acids The chemicals causing sourness of substance, is called acids .  These are not soapy to touch.  These turn blue litmus into red.  Example- Acetic acid(chemical in vinegar)  Bases The chemicals causing bitterness of substance, is called bases .  These are soapy to touch.  These turn red litmus into blue.  Example- baking soda, calcium hydroxide etc.  Indicator The substance used to test whether a substance is acidic or basic, are called indicator.  Example- Turmeric, litmus, china rose petals, phenolphthalein etc.  Litmus:A natural dye It is a natural indicator.  It is extracted from lichen.  When added to acid, it turns red.  When added to base, it turns blue.  Available in- Solution form, Paper strips Neutral solution The solution which donot change the colour of either red or blue litmus, is known as neutral solution.  Example- Sugar solution, water etc.  China rose as indicator China rose indicator turns acidic solutions to dark pink(magenta).  China rose indicator turns basic

Heat Energy that increases hotness of an object.  Temperature A reliable measure of the hotness of an object, is its temperature .  Thermometer A device used to measure temperature, is called thermometer .  Types of thermometer (i) Clinical thermometer (ii) Laboratory thermometer (iii) Maximum-minimum thermometer Clinical thermometer -The thermometer used to measure temperature of body, is called clinical thermometer.  -It consists of- glass tube,                           Bulb                           Mercury thread                           Kink -Range- 35°C to 42°C. -It has kink.  Clinical thermometer Laboratory thermometer -The thermometer used to measure temperature of an object, is called laboratory thermometer.  -It consists of- glass tube,                           Bulb                           Mercury thread                            -Range- -10°C to 110°C. -It doesn't have kink.  Maximu