# [2015] Gabrielle Punzalan: Semester Glog

In Glogpedia

by mikeeby
Last updated 5 years ago

Discipline:
Science
Subject:
Physics
8

Semester Glog

What matters in Matter

Gabrielle Punzalan

The Understanding of an Atom

Radioactivity: the process by which an unstable nucleus gives off nuclear radiationAlpha particles are basically helium nuclei composed of two neutrons and two protons. The protons give alpha particles a positive charge. Beta particles are fast moving electrons and are negatively charged. Gamma rays are a form of energy that is part of the electromagnetic spectrum. They are neutral. Alpha particles are heavy and deflect very little in a magnetic field. Beta particles are lighter and have the greatest deflection in a magnetic field. Gamma rays are neutral and so do not undergo any deflection.Nuclear fusion and nuclear fission are different types of reactions that release energy due to the presence of high-powered atomic bonds between particles found within a nucleus. In fission, an atom is split into two or more smaller, lighter atoms. Fusion, in contrast, occurs when two or more smaller atoms fuse together, creating a larger, heavier atom.The radioactive half-life for a given radioisotope is a measure of the tendency of the nucleus to "decay" or "disintegrate" in half each time.

Newton's 3 Laws of Motion

Transfer of Energy

Atomic number=number of protons per atom/number of electrons per neutral atomNumber of neutrons = mass number - atomic numberMass number = number of protons + number of neutronsIsotopes are atoms that have the same atomic number (and are therefore of the same element) but different mass numbers.Electron: a subatomic particle that has a negative chargeProton:a subatomic particle that has a positive charge and that is located in the nucleus of an atom; the number of protons in the nucleus is the atomic number, which determines the identity of an element Neutron:a subatomic particle that has no charge and that is found in the nucleus of an atomThe number of protons of an element indicates its atomic number. The atomic number, in turn, is the unique identifier that is used to name an element.

Binary ionic compounds(containing representative elements): a salt consisting of only two elements in which both elements are ions, a cation and an anion; Usually formed when metals bond to nonmetalsBinary covalent compounds: composed of two different nonmetal elements in which the atoms that are bonded share electrons rather than transfer electrons from one to the other.Synthesis: The combination of 2 or more simple substances to form a more complex substance.Decomposition: Two or more simpler substances form when a complex compound breaks apart.Single Replacement: Replacement of a metal in a compound by a more active metalDouble Replacement: the cations and anions switch between two reactants to form new products.

Conduction: the transfer of energy as heat through a materialConvection: the transfer of energy due to the movement of matterRadiation: the transfer of energy as electromagnetic wavesEnergy can be changed from one form to another. An object's gravitational potential energy is first transformed into kinetic energy, then into thermal energy when it hits the ground.

Acceleration: the rate at which velocity changes over time; an object accelerates if its speed, direction, or both change. To find average acceleration, you subtract starting velocity from final velocity, then divide it by the time it takes to change velocity.Velocity: the speed of an object in a particular direction To find average velocity, you divide the distance by the time it takes to travel that same distance, then you add your direction to it.Inertia: the tendency of an object to resist a change in motion unless an outside force acts on the objectForce: a push or a pull that acts upon an object as a results of its interaction with another object.Force is mass times acceleration, or F= m x a. This means an object with a larger mass needs a stronger force to be moved along at the same acceleration as an object with a small mass. In every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. Forces always come in pairs - equal and opposite action-reaction force pairs. The mass of an object is a measure of the amount of matter in the object. Weight is a measure of the force on the object caused by a gravitational field. In other words, weight is how hard gravity pulls on an object. Mass stays the same, but gravity changes depending on location.

Each row is called a period. All of the elements in a period have the same number of atomic orbitals.Each column is called a group. The elements in each group have the same number of electrons in the outer orbital. Those outer electrons are also called valence electrons. They are the electrons involved in chemical bonds with other elements. Ions are formed when atoms lose or gain electrons in order to fulfill the octet rule and have full outer valence electron shells. When they lose electrons, they become positively charged and are named cations. When they gain electrons, they are negatively charged and are named anions.

The Periodic Table

Solutions

Solution: a homogeneous mixture throughout which two or more substances are uniformly dispersedSolute: in a solution, the substance that dissolves in the solventSolvent: in a solution, the substance in which the solute dissolvesConcentration: the amount of a particular substance in a given quantity of a mixture, solution, or oreConductivity: the ability or power to conduct or transmit heat, electricity, or sound.Solubility: the maximum amount of a substance that will dissolve in a given amount of solvent at a specific temperature.There are two direct factors that affect solubility: temperature and pressure. Temperature affects the solubility of both solids and gases, but pressure only affects the solubility of gases.Bases have a slippery feel on fingers and taste bitter. They change litmus paper blue. Acids taste sour and create a stinging feeling on the mucous membranes. They change litmus paper red. They can react with bases to produce salts and water. They both conduct electricity depending on the dissociation of ions. Acids have a pH lesser than 7.0 and the lower it is, the stronger the acid becomes. Bases have a pH between 7 and 14. Higher the pH value, stronger will be the base. A pH level of 7 is a neutral substance which is water.