NCERT Chemistry class 11 - Online Notes : Stoichiometry

Here, we will discuss Stoichiometry from unit 1 of CBSE Class 11 Chemistry.

What is stoichiometry?

The relationship between the relative quantities of substances taking part in a chemical reaction or forming compounds, typically a ratio of whole integers.

Mole: The mole is the SI unit for the amount of substance. In short, it is written as “mol”. Mole is defined as the amount of a substance that contains the same number of entities (electrons, atoms, ions, or molecules) as the number of atoms in 12 grams of carbon-12 (12C). This is given by Avogadro’s number, in honor of an Italian physicist Amedeo Avogadro.

Avogadro number gives the number of units in one mole of any substance, which is equal to 6.0221×1023.The units may be electrons, atoms, ions or molecules depending on the nature of the substance and the reaction it undergoes. This means that one mole contains 6.023×1023 entities/units.

The importance of the mole unit is:

The mole unit allows us to relate the number of entities to the mass of a sample of those entities. For example; 1mol of 12C contains 6.022×1023 carbon-12 atoms and has a mass of 12 grams. This means that by the use of mole unit, we can count the number of entities by weighing the sample. If we find the weight of the sample of 12C to be 6 grams (g), so it means the sample of carbon-12 is 0.5 mol and it contains 3.011×1023
The mole maintains the same numerical relationship between mass on the atomic scale (atomic mass units, amu) and mass on a macroscopic scale (grams, g). This relationship is same for the elements as well as for the compounds. As explained here:

Comments

Last Minute Tips to Crack SSC CGL 2019-20 (Tier-I) Exam

Last-Minute Tips to Crack SSC CGL 2019-20 (Tier-I) Exam 1. Don’t read any new topic at the last moment · Try to avoid studying any new topic at the last moment. Just revise what you have already studied. 2. Don’t forget your Admit Card, Photograph and ID Proof · Take a print out of your admit card and original photo identity proof, 1 photo and photocopy of the ID proof. Reach the examination center before time to avoid any last-minute trouble. 3. Maintain your Speed & Accuracy and Maximize your Score · Speed and Accuracy are two important factors to crack any competitive exam. Speed will help in maximizing the attempts while accuracy will ensure that you don’t end up losing marks as the negative marking of 0.5 marks for wrong answers is there. 4. Attempt according to the strategy you followed in the mock tests · Make sure you attempt the easier section first. The exam should be attempted with the same strategy you fol...

Online cbse coaching class for 11 Mathematics

Online cbse Class 11 maths : Online coaching classes for 11 maths and for other subjects. We are here to solve students problem instantly, So that they can improve himself/herself. One to One Correspondence and Equivalent Sets Suppose the members of the family are dinning and plates are prepared on the table then there is a One to one correspondence between the set of family members and the plates prepared. We will indicate this correspondence by the symbol If each element of a set A is associated with one and only one element of a set B and each element of B is associated with one and only one element of set A, then the sets A and B are said to be in one to one correspondence. If both the sets are finite and if they are in one to one correspondence, it is obvious that they have the same number of elements. If two sets have the same number of elements, they are said to be equivalent sets. Using symbol, we write A B. Between two equivalent sets, a one to one corr...

Magnetic and non-magnetic material Class 6 Science

Magnetic and non-magnetic material Class 6 Science A magnet is a substance that is drawn to certain magnetic materials like iron, cobalt, and nickel. Magnets have the ability to draw iron to them. Natural magnets are rocks that naturally draw iron. Non-magnetic materials include things like wood, rubber, coins, feathers, leather, etc. that are not drawn to iron. Magnet characteristics It pulls magnetic materials, such as iron. The magnet's two ends are referred to as its poles. The magnet's diametrically opposed poles are drawn together. Heating, hammering, or dropping causes it to lose its characteristics. On the basis of properties types of Magnets Temporary magnets are those magnets that are magnetic for only a little duration. Typically, iron, cobalt, or nickel are used to make them. When they are close to the powerful magnet, they act like a magnet. When they are yanked away from the powerful magnet, they stop being magnetic. Permanent magnets are magnets that have magne...

Takshila Learning - Online Tutorials

Search This Blog