Chemistry
- alshevkun
- Feb 1
- 4 min read
The focus of this website is to simplify your learning process while keeping in mind our audience, the learners, so as a student i am here to provide you with my favourite trust worthy sources that i personally use when i study various chemistry topics!
this video is a lengthy but simple explanation, a basic overview of everything you need to know for grade 11- DP1 chemistry! this is a good start if you constantly find yourself lost over missing chunks of information!
States of matter:
Solid – Has a fixed shape and volume, with particles packed closely together.
Liquid – Has a fixed volume but takes the shape of its container, with particles that move more freely.
Gas – Has no fixed shape or volume, with particles that move rapidly and spread out.
There is also a fourth state, plasma, found in stars and lightning, where particles are highly energized and ionized.
these are two of my very favorite sources one being a simulation (diagram) which clearly displays the motion and structure of particles and the other a very good source of definitions.
States of matter in the environment
atomic structure
Protons – Positive charge (+), located in the center of the atom, called the nucleus.
Neutrons – No charge (neutral), also found in the nucleus alongside protons.
Electrons – Negative charge (-), moving around the nucleus in different energy levels or orbitals.
Think of the atom like a tiny solar system:
The nucleus (where protons and neutrons are) is the sun.
The electrons are like planets orbiting the sun at different distances (energy levels).
The number of protons determines what element the atom is (like hydrogen, oxygen, etc.), and the number of electrons helps balance the atom.
Periodic table
The periodic table organizes all known elements based on their atomic structure and properties. It has periods (rows) that show elements with increasing atomic number, where properties change from metals to nonmetals as you move left to right. The groups (columns) contain elements with similar chemical properties, and their group number often reflects the number of electrons in their outer shell. The table is also divided into metals (on the left, good conductors), nonmetals(on the right, poor conductors), and metalloids (elements with mixed properties). Additionally, the table is arranged into blocks (s, p, d, f) that represent the electron configurations of the elements. This structure helps predict how elements interact and behave chemically.
Chemical bonding
Metallic Bonding: This occurs between metal atoms. The atoms share their electrons freely in a "sea of electrons," which allows metals to conduct electricity and heat easily. This bonding is why metals are usually shiny, malleable (can be hammered into shape), and good conductors.
Ionic Bonding: This bond forms when one atom gives up electrons to another atom. One atom becomes positively charged (cation) and the other becomes negatively charged (anion). The opposite charges attract, holding the atoms together. This type of bonding happens between metals and nonmetals, like in sodium chloride (NaCl), or table salt.
Covalent Bonding: In this bond, atoms share electrons. It usually happens between nonmetals. For example, in water (H₂O), each hydrogen atom shares an electron with oxygen. This creates a stable bond between atoms and is why many nonmetals form gases or liquids at room temperature.
Acids bases and ph
Acids: These are substances that release hydrogen ions (H⁺) when dissolved in water. Acids taste sour (like lemon juice) and turn blue litmus paper red. Common examples include vinegar (acetic acid) and hydrochloric acid (HCl).
Bases: These are substances that accept hydrogen ions (H⁺) or release hydroxide ions (OH⁻) in water. Bases feel slippery and taste bitter (like soap). They turn red litmus paper blue. Examples include baking soda and soap.
pH: pH is a scale used to measure how acidic or basic a solution is. It ranges from 0 to 14:
A pH of 7 is neutral (like pure water).
A pH less than 7 is acidic.
A pH greater than 7 is basic (alkaline).
Endothermic and exothermic reactions
Endothermic Reactions: These reactions absorb energy (usually in the form of heat) from their surroundings. This means the surroundings get cooler. An example is the process of photosynthesis in plants, where energy from the sun is absorbed to make food.
Exothermic Reactions: These reactions release energy (usually in the form of heat) into the surroundings. This makes the surroundings warmer. A common example is burning wood or a fire, where energy is released as heat and light.
Solutions & rates of reaction
Solutions are mixtures where one substance (like sugar or salt) dissolves in another (like water). The substance that dissolves is called the solute, and the substance it dissolves in is called the solvent. For example, when you stir sugar in tea, the sugar dissolves, creating a solution.
Rates of reaction refer to how fast a chemical reaction happens. The speed can be influenced by several factors:
Temperature: Higher temperature makes the reaction happen faster.
Concentration: More reactants can lead to a faster reaction.
Surface area: Smaller pieces of a solid react faster than large chunks.
Catalysts: These are substances that speed up reactions without being used up.
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