Greek philosopher Democritus coined the term atom. Atom is derived from a Greek word atomos which means that it can not be cut. According to him, every matter is made up of tiny particles called atom.
Hence the correct answer to the first question is B-Atom.
According to Dalton's postulates, every matter consists of tiny spherical and indivisible particles called atom. Atoms of a specific element are same in size,mass and properties and varies from a different element.When a compound is formed,atoms always combine with other atoms with a fixed ratio
Hence the correct answer to the second question will be-A - The ratio of their masses is always the same.
J.J Thomson discovered electron from his Crooke' s tube experiment.The charge of electron is always negative .
Hence the correct answer to the third question will be B - Contains negatively charged particles.
As per Rutherford's atomic model, an atom consists of a massive positively charged core called nucleus.The total mass of the atom is appeared to be concentrated there. The electrons are revolving around the nucleus just like planets are revolving around the sun. The positive charge of the nucleus is due to the presence of protons. Most of the spaces in atom is empty.
As per the options given in the question,a huge stadium can be considered as atom.The the positively charged marble at the centre may considered as nucleus.
Hence the correct answer to this question will be D - It is like a huge stadium with positively charged marble at the center.
