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Equation Grade 10 SABIS SABIS A representation of a chemical reaction using the chemical formulas of the reactants and products.

Factors affecting rate of chemical reaction: SABIS Grade 10 SABIS ​ nature of reactants, concentration of reactants (or pressure if a gaseous reactant), surface area of a solid (or particle size), temperature, catalyst.

Boyle's Law ​ ​ The principle that states the volume of a given amount of gas is inversely proportional to its pressure at a constant temperature.

Surrounding Grade 10 SABIS SABIS The environment around a system where a chemical reaction is taking place.

Releasing Grade 10 SABIS SABIS Giving out, as in a reaction that releases heat is exothermic.

Essential Concepts of Atomic Structure: Grade 10 SABIS ​ Electrical Neutrality of Atoms : An atom is like a well-organized party where the number of positive guests (protons) equals the number of negative guests (electrons). This balance ensures that the overall mood (charge) of the party (atom) remains neutral. Formation of Positive Ions (Cations) : Imagine an atom as a generous friend who gives away one or more of its electrons. This act requires energy, like the effort it takes to give a gift. The result is a positive ion (or cation), where the number of protons exceeds the number of electrons. Formation of Negative Ions (Anions) : On the flip side, an atom can also be a gracious receiver, accepting one or more electrons. This usually releases energy, like the joy of receiving a gift. The result is a negative ion (or anion), where the number of electrons is greater than the number of protons. Stable Nucleus : A stable nucleus is like a timeless masterpiece. It can exist indefinitely, maintaining its composition and properties over time. Electron Position : Electrons are like free birds. They can be anywhere around the nucleus, and we can't predict their exact location at any given moment. However, they are more likely to be found closer to the nucleus, like birds prefer to stay near their nest. Atomic Number (Z) : The atomic number is like the ID card of an atom. It's the number of protons in the nucleus and equals the number of electrons in a neutral atom. It also determines the nuclear charge. Mass Number (A) : The mass number is like the total population of a city where protons and neutrons live. It's the total number of protons and neutrons (nucleons) in a nucleus and represents the mass of a given nucleus. Nuclear Representation : A nucleus of an atom is represented by ZX^A, where X is the element’s symbol, Z is the atomic number (number of protons), and A is the mass number (number of nucleons). Quarks : Protons and neutrons are like a bag of tiny particles called quarks. These are the fundamental constituents that make up protons and neutrons. Isotopes : Isotopes are like siblings. They belong to the same element family (same atomic number), but they have different weights (mass numbers). They have the same nuclear charge, the same number of electrons, and react chemically in the same way. For example, hydrogen has three isotopes: hydrogen, deuterium, and tritium. Similarly, oxygen has three isotopes: oxygen-16, oxygen-17, and oxygen-18. Despite their differences in mass, they are all still recognized as hydrogen or oxygen, respectively.

< Back Chemical bonding This is placeholder text. To change this content, double-click on the element and click Change Content. This is placeholder text. To change this content, double-click on the element and click Change Content. Want to view and manage all your collections? Click on the Content Manager button in the Add panel on the left. Here, you can make changes to your content, add new fields, create dynamic pages and more. You can create as many collections as you need. Your collection is already set up for you with fields and content. Add your own, or import content from a CSV file. Add fields for any type of content you want to display, such as rich text, images, videos and more. You can also collect and store information from your site visitors using input elements like custom forms and fields. Be sure to click Sync after making changes in a collection, so visitors can see your newest content on your live site. Preview your site to check that all your elements are displaying content from the right collection fields. Previous Next 🔬 Chapter 4: Chemical Bonding 🔬 Learning Outcomes 🎯: Describe different types of bonding using dot-and-cross diagrams, including ionic, covalent, and co-ordinate (dative covalent) bonding. Explain shapes and bond angles in molecules using electron-pair repulsion. Describe covalent bonding in terms of orbital overlap, sigma and pi bonds, and hybridization. Explain terms like bond energy, bond length, and bond polarity. Describe intermolecular forces based on permanent and induced dipoles, hydrogen bonding, and metallic bonding. Deduce the type of bonding present from given information. (Page 48) Van der Waals’ Forces 💨: Van der Waals’ forces are weak forces of attraction between atoms or molecules. They arise due to temporary dipoles set up by the movement of electron charge clouds. These forces increase with the increasing number of electrons and contact points between molecules. They play a significant role in the boiling points of noble gases and other substances. (Page 14) Bond Length and Bond Energy ⚛️: Double bonds are shorter and stronger than single bonds. Bond energy is the energy needed to break one mole of a given bond in a gaseous molecule. Bond strength influences the reactivity of a compound. (Page 6) Metallic Bonding 🧲: Metals have a giant metallic structure with positive ions surrounded by a sea of delocalized electrons. This structure explains why metals are good conductors of electricity and have high melting points. (Page 22) Hydrogen Bonding and Boiling Point 🌡️: Hydrogen bonding can cause compounds to have higher boiling points than expected. Water has a much higher boiling point and enthalpy change of vaporization due to extensive hydrogen bonding. (Page 17)

Variation of PE as two H atoms approach each other Grade 10 SABIS ​ The variation of potential energy (PE) as two hydrogen atoms approach each other is influenced by the interplay between attractive and repulsive forces. As the atoms move closer together, the potential energy undergoes significant changes, which can be understood in terms of the interaction between their electron clouds and the electrostatic forces between the nuclei and electrons. When two hydrogen atoms are far apart, the electron clouds of each atom experience only weak attractive forces. At this point, the potential energy is relatively low since there is little interaction between the atoms. As the atoms start to approach each other, the electron clouds of the two atoms begin to overlap. The overlapping electron clouds create an attractive force between the atoms known as the London dispersion force. This force arises due to the temporary fluctuations in electron distribution and induces a slight attraction between the atoms. As the atoms get closer, the potential energy decreases further as the attractive forces become more significant. However, as the atoms continue to approach each other, the repulsive forces between their positively charged nuclei become more pronounced. These repulsive forces arise due to the electrostatic repulsion between the like charges of the protons in the nuclei. The potential energy starts to increase rapidly as the repulsion outweighs the attraction. At a certain point, known as the equilibrium bond length, the attractive and repulsive forces balance each other, resulting in the lowest potential energy between the two hydrogen atoms. This equilibrium bond length corresponds to the most stable configuration of the hydrogen molecule, where the potential energy is at its minimum. If the atoms are brought even closer together than the equilibrium bond length, the repulsive forces dominate, causing the potential energy to increase sharply. This indicates an unfavorable arrangement, and the atoms will experience a strong repulsion. The variation of potential energy as two hydrogen atoms approach each other can be visualized using a potential energy diagram. The diagram shows the change in potential energy as a function of the distance between the atoms, highlighting the regions of attraction, equilibrium, and repulsion. In summary, the variation of potential energy as two hydrogen atoms approach each other is determined by the balance between attractive and repulsive forces. Initially, there is a weak attraction due to electron cloud overlap, leading to a decrease in potential energy. However, as the atoms get closer, the repulsive forces between their nuclei become dominant, causing the potential energy to increase. At the equilibrium bond length, the potential energy reaches its minimum, indicating a stable configuration. Beyond this point, further approach results in a rapid increase in potential energy due to strong repulsion. Understanding the variation of potential energy provides insights into the stability and bonding behavior of hydrogen molecules.

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Conservation of molecules? Grade 10 SABIS SABIS Molecules are not necessarily conserved in chemical reactions.