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• Non-metals are poor conductors, brittle, insulators, and have low density.
• Protons are positively charged subatomic particles found within the nucleus of the atom, with an approximate mass of 1 atomic mass unit and a charge of +1 elementary charge.
• Neutrons are neutrally charged subatomic particles found within the nucleus of the atom alongside protons, with an approximate mass of 1 atomic mass unit and no electric charge.
• Electrons are negatively charged subatomic particles that orbit around the nucleus of an atom, with a smaller mass compared to protons and electrons.
• Groups, also known as families, are the vertical columns of elements in the periodic table.
• Elements within the same group share similar chemical properties because they have the same number of valence electrons.
• There are 18 groups in the periodic table.
• Periods are the horizontal rows of elements in the periodic table, each period corresponds to a new electron shell or energy level being filled with electrons.
• Niels Bohr’s model of the atom was a significant development in early quantum theory, introducing quantized energy levels for electrons, limiting them to specific orbits around the nucleus.
• Bohr's atomic model explained the stability of atoms and quantized spectral lines in light emission and absorption.
• While successful for hydrogen, Niels Bohr's model was later replaced by quantum mechanics for a more comprehensive understanding of atomic behaviour.
• There are 7 periods in the periodic table.
• Electrons are located outside the nucleus where they orbit.
• The nucleus of an atom has a positive charge due to the presence of protons, which are positively charged subatomic particles.
• Electrons, carrying a negative charge, orbit the nucleus, resulting in an electrically neutral atom.
• Metals are excellent conductors of both electricity and heat due to their abundance of free electrons that can move freely and carry electric current or thermal energy.
• A controlled variable is what is kept the same throughout the experiment so that they don’t affect the results.
• Variables are not consistent or having a fixed pattern; liable to change.
• Dry cells use a solid or paste electrolyte instead of a liquid solution.
• The positive charge in the nucleus is vital for stabilizing the atom, as it creates an attractive force that holds electrons in their specific energy levels, ensuring the structural integrity of the atom.
• Metals have a characteristic shiny and reflective appearance, which is due to their ability to reflect light on their smooth surfaces.
• The use of a solid or paste electrolyte makes dry cells more portable and less prone to leakage compared to wet cells.
• The substance that undergoes oxidation is often referred to as the reducing agent.
• The overall reaction is represented by the combination of these two half-reactions.
• The electrolyte in a wet cell ensures everything runs well and prevents any issues that might slow down or stop the battery from working.
• A dependant variable is what is measured in an experiment; It depends on the changes you make to the independent variable.
• Wet cells use an electrolyte that helps electricity flow smoothly between the positive and negative sides and ensures the chemical reactions needed for the battery to work can happen.
• In a redox reaction, reduction and oxidation occur simultaneously, and the electrons lost in the oxidation half-reaction are gained in the reduction half-reaction.
• An independent variable is what is intentionally changed in an experiment.
• Ductility and lustrousness are two more properties of metals.
• The electrolyte serves as a medium for the flow of ions between the two electrodes, the anode (negative terminal) and the cathode (positive terminal).
• Oxidation involves the loss of electrons by a chemical species.
• A cell refers to an electrochemical cell, which is a device that converts chemical energy into electrical energy through a redox reaction.
• Cells are the building blocks of batteries and power sources that provide electrical energy for various applications.
• Wet cells use liquid electrolyte solution to facilitate the chemical reactions that produce electrical energy.