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Dalton's atomic theory states that:
All matter is made up of very tiny particles called atoms.
Atoms are indivisible particles that cannot be created or destroyed in a chemical reaction.
Atoms of a given element are identical in mass and chemical properties.
Atoms of different elements have different masses and chemical properties.
Atoms combine in a ratio of small whole numbers to form compounds.
The relative number and kinds of atoms are constant in a given compound.
Drawbacks of Dalton's atomic theory:
Dalton's atomic theory states that atoms are indivisible but now we know that atoms can be further divided into much smaller particles such as neutrons, protons, and electrons.
Dalton's atomic theory states that all atoms of the same element have the same masses. Still, it is now found that atoms of the same element can also have different masses for example isotopes.
Dalton's atomic theory states that atoms of different elements have different masses. But it is now known the atoms of other elements can have the same masses.
An atom has two electrons in the outermost m shell. State its electronic configuration,atomic number,valency,whether metal or non metal,number of protons,name of the element.