1 – The atoms of an element can exist in different types. These are called isotopes. 2 – Isotopes are atoms that have the same number of protons and electrons , but a different number of neutrons. 3 – Changing the number of neutrons in an atom does not change …
1 – Each atom is made up of a nucleus and a number of electrons moving in orbital shells at great distances from the nucleus. 2 – Electrons are particles spinning and revolving around the nucleus of the atom similar to the earth rotating on its own axis as it …
1 – An atom is the smallest particle of an element still having the same chemical properties of the element. 2 – Atoms are the basic building blocks of matter that make up everyday objects. A desk , the air , even you are made up of atoms! 3 – …
1 – Oxygen is the most vital nutrient for the human body. You can survive several weeks without food , several days without water , but you cannot survive more than a few minutes without oxygen. 2 – It is a simple and indisputable fact – oxygen is necessary to …
1 – The noble gases are a group of elements in the periodic table. They are located to the far right of the periodic table and make up the eighteenth column. 2 – The elements that make up the family of noble gases include helium , neon , argon , …
1 – Around 78% of the atmosphere is nitrogen. 2 – Nitrogen is also found in all living organisms and is indispensable for survival of life on Earth. 3 – The nitrogen cycle , in which atmospheric nitrogen is converted into different organic compounds , is one the most crucial …
1 – Hydrogen can be considered as the simplest element in existence. 2 – Hydrogen is the only element that does not contain any neutrons. It contains one proton and one electron. Because of this , it is not a part of any group or family on the periodic table. …
1 – Carbon dioxide , or CO2 , is a gas composed of one carbon and two oxygen atoms. 2 – Carbon dioxide makes up about 0.037 percent of the air. 3 – Slight as that amount is , plants and animals depend upon it for life. It is a …
1 – The Earth’s atmosphere is divided into several layers. The lowest region, the troposphere, extends from the Earth’s surface up to about 10 kilometers (km) in altitude. 2 – The next layer, the stratosphere, continues from 10 km to about 50 km. Most atmospheric ozone is concentrated in a …
1 – A greenhouse is a building built of any material that passes sunlight , usually glass , or plastic. 2 – People grow tomatoes and flowers and other plants in them. A greenhouse stays warm inside , even during winter , the heat is trapped by the glass and …