Question 1: Compare the properties of electrons, protons and neutrons. Answer: Electron Proton Neutron Electrons are present outside the nucleus. Protons are present in the nucleus. Neutrons are present in the nucleus of the atom. They are negatively charged. They are positively charged. They are neutral in charge. Mass of electrons is negligible. The mass …
Question 1: A 0.24 g sample of the compound of oxygen and boron was found by analysis to contain 0.096 g of boron and 0.144 g of oxygen. Calculate the percentage composition of the compound by weight. Answer: Mass of boron = 0.096g (Given) Mass of oxygen = 0.144g (Given) Mass of sample = 0.24g …
Question 1. What is meant by a substance? Answer: A substance made up of a single type of particle is known as a pure substance. Question 2. List the points of differences between homogeneous and heterogeneous mixtures. Answer: S. No. Homogeneous Heterogeneous 2 It has a uniform composition. Its composition is non- uniform. 3 It …
Question 1: Convert the following temperatures to the Celsius scale. (a) 300 K (b) 573 K Answer: Using the formula: – T (°C) = T (K) – 273.15 300K = (300 – 273) = 27O C 573 K = (573 – 273) = 300O Cnaphthalene Question 2: Convert the following temperatures to the Kelvin …
Very Short and Short Answer Type Questions What are colloids? Give examples. What are emulsions? Give examples. What are sols? Give examples. Define Aqueous and non-aqueous solutions. Give an example of liquid in a liquid solution. Write down the properties of compounds. What is a saturated solution? Give examples. If 50 ml of acetone is …
Very short and Short Answer Type Questions How can we separate a mixture of two liquids? Name the process to separate the particles of the colloid. How do we test the purity of substances? Gases can be easily compressed but not liquids. Why? Which gas is called dry ice? Why? Differentiate between the three states …
Introduction The matter is composed of atoms and molecules. Earlier it was believed that the atom is indivisible. By the end of the nineteenth century, scientists revealed the presence of charged particles in an atom. Atoms are composed of 3 subatomic particles- electron, neutron and neutron. Electrons have a negative charge; protons have a positive …
Introduction We all know that matter is anything that occupies space and has mass. The idea of divisibility of matter was considered long back in India, around 500 BC. An Indian philosopher Maharishi Kanad, postulated that if we go on dividing matter (padarth), we shall get smaller and smaller particles. Ultimately, a stage is …
Introduction Everything around us is made of matter. For example, wood, paper etc. All the matter around us is not pure. It can be pure or impure. https://www.youtube.com/watch?v=fXmosf3yblA&list=PLAVY2tu_2M4jDkdNv8QJLwQi0eQVJ4Ryd&index=4
