John Dalton
English Chemist, 1800s
The SOlid Sphere MODEL
Unique Elements
He proposed that every element is made up of atoms that are all the same type. For example, all hydrogen atoms are identical and different from oxygen or any other element. This idea introduced the concept that each element has its own specific kind of atom.
Formation of compounds
Dalton suggested that compounds are made when atoms of different elements come together in specific, fixed ratios. So, a molecule of water always has two hydrogen atoms and one oxygen atom, and this ratio is consistent.
Chemical Reactions
According to Dalton, chemical reactions involve the rearrangement of these atoms. Atoms themselves are not created or destroyed in these reactions; they just get rearranged to form new substances. This idea was crucial for understanding the conservation of mass.
ATOMS AS SOLID SPHERES
John Dalton's solid sphere model in 1803. This theory states that all objects are made of particles called atoms and that they are solid spheres that cannot be divided further into smaller particles, he imagined atoms as tiny, solid balls just like miniature billiard balls.
LAw of multiple proportions
Dalton’s theory also supported the law of multiple proportions, which means if two elements can combine in more than one way, the different combinations of these elements will always be in simple whole-number ratios.