Science

• From Latin word “scientia." which means "knowledge".
• Any methodological activity. such as observational. experimental investigation and theoretical explanation of natural phenomena.
• Systematized knowledge based on facts.

Divisions of Science

• Social Science
• Political Science
• History
• Mathematics
• Natural science

Branches of Natural Science

• Physical Science - Dealing with non-living things.
• Biological Science - Dealing with living things.

Scientific Method

• An orderly. logical and rational manner of solving problems.
• Enables and Ieads scientists towards unveiling the truths about observable phenomena and construct their clear representations.

Cell Theory

• Describes or explains what a cell is.
• Cell is the basic component of a living organism.
• New cells are produced from existing cells.
• Cell is the building block of life.

Kinds of Cell

• Prokaryotic - has no nucleus; ex. Bacteria
• Eukaryotic - has true nucleus; ex. Mammals

Electromagnetism

• Magnetism  - derived from Magnesia, an island in the Aegean Sea
• Magnet  - an object that attracts magnetic objects like metals
• A magnet has two poles, north and south.
• Like poles repel, unlike poles attract.
• Generator - a device that changes mechanical energy to electrical energy
• Motor - a device that changes electrical energy to mechanical energy

Mixtures

• Physical combination of 2 or more substances which can be separated by mechanical means.

• Homogeneous mixture 
• a mixture in which the molecules are thoroughly mixed: a mixture that is uniform throughout.
• Solutions are homogeneous mixtures. The components of solution are solute, which is the dissolved particles. and the solvent. which is the dissolving particles.

• Heterogeneous mixture
• Suspensions - heterogeneous mixture where particles are too large that they settle at the bottom of the container.
• Colloids - heterogeneous mixtures whose particles are not large enough to settle nor small enough to be dissolved, like the Tyndall Effect. which is the scattering of light by the particles.

Methods of Separating Mixtures

• Filtration - use of filter paper to separate liquid from solid components.

               Filtrate - liquid that passes through the filter paper.
               Residue - substance that did not pass through the filter paper.

• Decantation - pouring off a layer of liquid from a mixture.
• Magnetism - use of magnets to separate magnetic materials from the nonmagnetic ones.
• Centrifugation - substance is subjected to circular or rotational motion in a centrifuge.
• Distillation - liquid is set to boiling. Vapour is collected and later cooled to condense.
• Chromatography - passing mixture in solution or suspension or as a vapour (as in gas chromatography) through a medium in which the components move at different rates.