Matter, Atoms, and Electric Charge: A Physics Fundamentals

Posted on Nov 28, 2024 in Chemistry

Mass and Matter

Mass is related to the amount of matter and measures the inertia of a body, exerting gravitational action. A body of 10 kg has twice the inertia of a body of 5 kg. The mass of Jupiter is about 310 times the mass of Earth, resulting in a 310 times larger gravitational force. Density is calculated as mass/volume. The mass of an object measures its inertia, while its weight on Earth is the force drawing it towards the planet.

Material Systems

A material body is any form of matter with defined limits. A material system is any form of matter without precise boundaries, whether by nature or extension.

Observation Methods

  • Direct Inspection: Requires instruments like optical microscopy, electron microscopy, or scanning tunneling microscopes.
  • Indirect Inspection: Involves creating models and laws from observable macroscopic experimental facts.

Powers of Ten

Positive Powers of Ten

Multiply 1 x 104

Negative Powers of Ten

Divide one by ten four times: 1/10 x 1/10 x 1/10 x 1/10

A body or material system can be many orders of magnitude larger than another, indicated by the exponent of the power of ten when dividing their respective sizes.

Atoms and Electric Charge

Atoms

All matter consists of atoms. The size of a hydrogen atom is 0.000 000 0001 m.

Electrical Phenomena

  • Rubbing certain materials produces electrical phenomena.
  • Electrical phenomena can be attractive or repulsive.

Electric Charge

  • Electric charge causes attraction and repulsion in nature.
  • There are two types of electric charge: positive and negative.
  • Bodies are usually electrically neutral. When they exhibit a charge, they are electrified or “charged.”
Charge Interactions

Like charges repel (e.g., two positively charged materials or two negatively charged materials). Unlike charges attract.

Electrons

  • Electrons are part of atoms.
  • They have a mass 1840 times smaller than the smallest atom.
  • They have a negative electric charge.

It is impossible to strip electrons of their negative charge; it is an intrinsic property.

Protons

  • Protons are found in atomic nuclei.
  • They have a positive electric charge.
  • They have a mass similar to that of a hydrogen atom.

Neutrons

  • Neutrons are in atomic nuclei with protons.
  • They have no electrical charge (neutral).
  • They have a mass almost equal to that of a proton.

Atomic Structure

Atoms consist of a nucleus (protons and neutrons) and a surrounding electron cloud. The atom’s interior is comparable to a tiny solar system: the nucleus is the sun, and electrons are the planets.

Electron Transfer

While the number of protons in an atom is constant, atoms can gain or lose electrons due to nearby atoms, electric shocks, high temperatures, etc.

Chemical Formulas

Compounds are represented by chemical formulas. Formulas include symbols for the atoms involved and numbers (subscripts) indicating the quantity of each atom in a molecule or the ratio of ions in ionic compounds.

Example: Hydrogen Sulfide (H2S)
  • The compound is made up of hydrogen (H) and sulfur (S).
  • The molecule consists of two hydrogen atoms and one sulfur atom.
Example: Sodium Chloride (NaCl)
  • The compound is composed of sodium (Na) and chlorine (Cl).
  • There is one sodium ion for each chloride ion.