What contribution did Robert Millikan make to the atomic theory?

His earliest major success was the accurate determination of the charge carried by an electron, using the elegant “falling-drop method”; he also proved that this quantity was a constant for all electrons (1910), thus demonstrating the atomic structure of electricity.

What was Robert Millikan’s discovery?

Elementary chargeMagnitude
Robert Andrews Millikan/Discoveries

Why was Millikan discovery important?

Millikan’s experiment is important because it established the charge on an electron. Millikan used a very simple a very simple apparatus in which he balanced the actions of gravitational, electric, and (air) drag forces. Using this apparatus, he was able to calculate that the charge on an electron was 1.60 × 10⁻¹⁹ C.

When did Henry Moseley contribute to the atomic theory?

Henry Moseley was an outstandingly skilled experimental physicist. In 1913 he used self-built equipment to prove that every element’s identity is uniquely determined by the number of protons it has.

When did Ernest Rutherford contribute to the atomic theory?

1911
In 1911, he was the first to discover that atoms have a small charged nucleus surrounded by largely empty space, and are circled by tiny electrons, which became known as the Rutherford model (or planetary model) of the atom.

What contribution did Robert Millikan make in the study of atomic structure discuss how he came up with his result?

Robert Millikan’s accomplishments were the design and fine-tuning of experiments which unambiguously confirmed the most important scientific theories of his time, providing the implications for atomic theory. His oil drop experiment confirmed the existence of the electron and accurately determined its charge.

How did Robert Millikan’s oil drop experiment change scientists view of the atom?

Robert Millikan was able to determine the mass of an electron by using charged oil drops. Electrons have such a small mass, they were believed to be massless. Millikan’s experiment determined that the electrons did, indeed, have mass.

What did Henry Moseley discover about the atom?

Known as Moseley’s law, this fundamental discovery concerning atomic numbers was a milestone in advancing the knowledge of the atom. In 1914 Moseley published a paper in which he concluded that the atomic number is the number of positive charges in the atomic nucleus.

What did Neil Bohr contribute to the atomic theory?

In 1913, Niels Bohr proposed a theory for the hydrogen atom, based on quantum theory that some physical quantities only take discrete values. Electrons move around a nucleus, but only in prescribed orbits, and If electrons jump to a lower-energy orbit, the difference is sent out as radiation.

What did John Newland contribution to the periodic table?

British chemist John Newlands was the first to arrange the elements into a periodic table with increasing order of atomic masses. He found that every eight elements had similar properties and called this the law of octaves. He arranged the elements in eight groups but left no gaps for undiscovered elements.

What did Rutherford contribute to the model of the atom?

Ernest Rutherford is known for his pioneering studies of radioactivity and the atom. He discovered that there are two types of radiation, alpha and beta particles, coming from uranium. He found that the atom consists mostly of empty space, with its mass concentrated in a central positively charged nucleus.

What did Millikan contribute to the atomic theory?

Robert Millikan’s primary contribution to atomic theory came as a result of his oil-drop experiment, which measured an electron’s charge. Previously, J.J. Thomson had suggested the hypothesis that an electron’s mass was at least 1,000 times less than the mass of the tiniest atom.

What was Millikan’s contribution to atomic theory?

–  He used the oil drop experiment to find the charge of an electron. – He his also known for his contributions of work on the photoelectric effect. – He found a way to calculate mass of electrons and and positively charged atoms.

When did Robert Millikan contribute to atomic theory?

In 1910 Robert Millikan succeeded in precisely determining the magnitude of the electron’s charge. Small electrically charged drops of oil were suspended between two metal plates where they were subjected to the downward force of gravity and the upward attraction of an electrical field.

What did Robert Millikan discover about the electron?

Robert Millikan made numerous discoveries in the fields of optics, electricity and physics. One of his most important discoveries was the determination of the charge of an electron. His calculations were instrumental in proving that electrons are fundamental, or indivisible, particles.