The atom

Fundemental chemical Laws:

Law of conservation of mass: Mass is neither creared nor destroy.

Law of definite proportion: A given compound always contains exactly the same proportion of elements by mass.

Law of multiple proportions: When two elements from a series of compounds, the ratios of the masses of the second element that combine with 1 gram of the first element can be reduced to small whole numbers ration.

  • Example: H2O & H2O2 The ratio between the masses of oxygen will be a small whole number 2

Daltons Atomic theory: Atoms of a give element are identical; ie. Atmos of different elemetns are differenet in fundemental ways.

  • Chemical reactions involve reorganization of the atoms. The atoms are not charged themseleves/

Cathode function:

  • Two metal plates are connected to a high voltage source, the cathode will make a an invisible ray towards the anode across the vaccuum.

    • Cathode rays:

      • Always the same regardless of the metal used as the cathode

      • They are deflected by magnetic field as if they were negatively charged particles.

Isotopes: The version of the same element with different masses. Where some elements have different number of neutrons bu thte same number of proptons.

  • Some of them are radioactive. Ie. Their nucleus is unstable.

  • They are reffered to bu their element name and mass.

Atomic mass:

Mass number= number of protons + number of neutrons

avg atomic mass= (mass of isotope*abudenance as a decimal) + (mass of the next isotope)(abundance as a decimal)

= (35)(0.7553) + (37×02447)

= 35.49 amu