Imp points 👍 you must know and clear your concepts

 Important points 👍 you must know and clear your concepts 

🧩Dalton’s Atomic Theory:

➖Every matter consists of indivisible atoms.

➖Atoms can neither be created nor destroyed.

➖Atoms of a given element are identical in  properties

➖ Atoms of different elements differ in properties.

➖Atoms of different elements combine in a fixed ratio to form molecule of a compound.

🧩Precision and Accuracy: 

➖Precision: Closeness of outcomes of different measurements taken for the same quantity. 

➖Accuracy: Agreement  of experimental value to the true value 

🧩Laws of Chemical Combination:

➖Law of conservation of mass: 

“For any chemical change total mass of active reactants are always equal to the mass of the product  formed”

➖Law of constant proportions:

 “A chemical compound always contains same elements in definite proportion by mass and it does not  depend on the source of compound”.

➖Law of multiple proportions:

 “When two elements combine to form two or more than two different compounds then the different masses  of one element B which combine with fixed mass of the other element bear a simple ratio to one another” 

➖Law of reciprocal proportion: 

“ If two elements B and C react with the same mass of a third element (A), the ratio in which they do so will    be the same or simple multiple if B and C reacts with each other”.

➖Gay Lussac’s law of combining volumes: 

“At given temperature and pressure the volumes of all gaseous reactants and products bear a    simple whole number ratio to each other.