What is molecule in biology?
A molecule is the smallest unit of matter that has distinctive chemical and physical properties. A molecule owns a definite size and mass. Two or more atoms (same or different) held together by a chemical bond form a molecule wherein the ratio of two atoms is fixed in an element.
What is a molecule short definition?
A molecule is two or more atoms connected by chemical bonds, which form the smallest unit of a substance that retains the composition and properties of that substance.
What is a molecule Class 9 example?
A group of atoms that combine together and form a single entity. Ex- H 2 O where 2 atom of H and 1 of oxygen forms a molecule of water.
What is molecular mass class 9?
Molecular mass or molecular weight is the mass of a molecule. “The molecular mass of a substance is the sum of the atomic masses of all the atoms in a molecule of the substance”. It is expressed in the atomic mass unit(u).
What is a molecule for kids?
A molecule is two or more atoms joined (or “bonded”) tightly together. The number and kinds of atoms in a molecule, and the way they are arranged, determine what substance it makes. For example, a molecule made of two oxygen atoms joined to one carbon atom forms carbon dioxide, a colorless gas.
Why is it a molecule?
Whether something is a molecule or not depends on the type of bond that is formed when its atoms join together. In general, electrons can be shared between atoms (a molecular bond) or electrons can be completely removed from one atom and given to another (an ionic bond). Molecules have molecular bonds.
What are 3 types of molecules?
Molecules are of three types: Molecule of an atom, Molecule of an element and Molecule of a compound.
What is atom in biology?
An atom is the smallest component of an element that retains all of the chemical properties of that element. For example, one hydrogen atom has all of the properties of the element hydrogen, such as it exists as a gas at room temperature, and it bonds with oxygen to create a water molecule.
What is molecule class 9 chapter 3?
Answer: The smallest particle of matter, which can take part in a chemical reaction is called atom. Question 5. Define molecule. Answer: The smallest particle of an element or compound which can exist independently is called molecule.
What is molecule class 2?
(1) A molecule is the smallest particle in a chemical element or compound that has the chemical properties of that element or compound. Molecules are made up of atoms that are held together by chemicals bonds.
What is a molecule Class 9 very short answer?
A molecule is the smallest thing a substance can be divided into while remaining the same substance. It is made up of two or more atoms that are bound together by chemical bonding.
What is 1 mole?
A mole is defined as the amount of a substance that contains 6.022 X1023 entities like particles, atoms, ions, molecules, etc. of the given substance. A mole measures the number of atoms, ions, or molecules.
What is atomicity class 9?
The number of atoms present in a molecule of an element is called its atomicity.
What is Valency Class 9?
Valency is simply equal to the number of electrons gained, lost or shared by an atom of an element to achieve the nearest noble gas configuration. For example, the valency of sodium (Na) is 1, magnesium (Mg) is 2, Chlorine (Cl) is 1 etc.
What are the 2 types of molecules?
A molecule may be homonuclear, that is, it consists of atoms of one chemical element, e.g. two atoms in the oxygen molecule (O2); or it may be heteronuclear, a chemical compound composed of more than one element, e.g. water (two hydrogen atoms and one oxygen atom; H2O).
What is difference between atom and molecule?
Atom is the smallest particle of any element, whereas a molecule is the smallest particle of the compound. 2. Atoms may or may not present independently whereas molecules exist independently.
Is water a molecule?
Atoms join together to form molecules. A water molecule has three atoms: two hydrogen (H) atoms and one oxygen (O) atom. That’s why water is sometimes referred to as H2O. A single drop of water contains billions of water molecules.