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faab97ab-1ab7-4b63-8e91-a5f48ea4bdb7 Types of Chemical Reactions and Solution Stoichiometry Oxidation–Reduction (Redox) Reactions Summary

Lesson 37 Structure of the atom and the periodic table Chapter 7 SABIS Grade 10 Part 1 Lesson 37 Structure of the atom and the periodic table Chapter 7 Structure of the atom and the periodic table Lesson 1 Content 7.1 Structure of the Atom 7.1.1 The nuclear atom 7.1.2 What the nucleus contains 7.1.3 Nuclei of atoms of the same element 7.1.4 Neutral atoms and the formation of ions 7.1.5 Mass of subatomic particles 7.1.6 The nuclear model 7.1.7 The sizes of atoms 7.1.8 Atomic number 7.1.9 Mass number Symbols to refer to elements in chemical reactions Symbols to refer to atomic nuclei 7.1.10 Isotopes Pre-Requisite Questions: What are the three main particles that make up an atom? 🧐 Can you recall what an ion is? 💡 What is the significance of the atomic number of an element? 🤔 What do you understand by the term 'isotopes'? 🤨 What's the main difference between a cation and an anion? 🙄 (Answers: 1. Protons, Neutrons, and Electrons. 2. An ion is an atom or molecule with a net electric charge due to the loss or gain of one or more electrons. 3. The atomic number of an element represents the number of protons in its nucleus. 4. Isotopes are variants of the same element with the same number of protons but different numbers of neutrons. 5. Cations are positively charged ions, and anions are negatively charged ions.) 🎯Lesson Begins 📍What's Inside the Atom? Atoms are like the invisible LEGO blocks that make up everything we see and touch. An atom consists of subatomic particles—protons, neutrons, and electrons. 😲 Imagine an atom as a tiny solar system, with a nucleus at the center like the sun and electrons whizzing around like planets. 🌞🪐 🏟️Nuclear Atom The center, or nucleus, of the atom is where we find the protons and neutrons. Protons carry a positive charge (like the positive vibe in a party 🥳), and neutrons have no charge—they're the cool, neutral folks at the party. ⚖️ 📏Size of an Atom Atoms are incredibly tiny. The diameter of an atom—the distance between two adjacent nuclei—is in the order of 10^-10 meters. 📏That's about a hundred million times smaller than an apple seed! 🍎 The diameter of the nucleus is even tinier, at about 10^-14 meters. Picture a pea in the middle of a football stadium—that's how empty an atom is! 🏈🏟️ ⚖️Mass of an Atom The protons and neutrons together are known as nucleons. They're the heavyweight champs of the atom, with most of the mass concentrated in the nucleus. 🏋️♂️ On the other hand, electrons are featherweights, weighing about 1/1840 the mass of a proton. 🔋Charge of an Atom An atom, like your favorite superhero, is electrically neutral—meaning it has an equal number of positive protons and negative electrons, balancing each other out. 💪 🔄Formation of Ions Ions are formed when atoms lose or gain electrons. Losing an electron forms a cation (a positively charged ion), kind of like losing weight and becoming positively happier! 🤸♂️🎈 Conversely, gaining an electron forms an anion (a negatively charged ion), like gaining responsibilities and getting negatively stressed! 😓📚 🔢Atomic Number and Mass Number Think of the atomic number (Z) as the ID card of an element—it tells us the number of protons in an atom. In a neutral atom, it also equals the number of electrons. The mass number (A), on the other hand, is like the total weight of an atom—it adds up the number of protons (P) and neutrons (N) in an atom. Simple math, right? 1️⃣2️⃣3️⃣ 🎭Isotopes Isotopes are like the twins of an element. They have the same atomic number, but a different mass number. For example, hydrogen (1H), deuterium (2H), and tritium (3H) are all isotopes of hydrogen—they all have 1 proton, but a different number of neutrons (0, 1, and 2 respectively). It's like different flavors of your favorite ice cream—different tastes, but still ice cream! 🍨 Review Questions: What is the order of the diameter of an atom? a. 10^-10 m b. 10^-14 m c. 10^10 m d. 10^14 m What do we call an atom that has gained or lost electrons? a. Isotope b. Ion c. Cation d. Neutron Which particle is found inside the nucleus of an atom? a. Protons b. Neutrons c. Electrons d. Both a and b Which of these is the best definition of isotopes? a. Atoms of the same element with the same number of protons but different numbers of neutrons. b. Atoms with the same number of protons but different number of electrons. c. Atoms with the same number of neutrons but different number of protons. d. None of the above An atom that has more protons than electrons is called? a. A cation b. An anion c. A neutron d. An electron (Answers: 1. a, 2. b, 3. d, 4. a, 5. a) Quiz Click on the below and join the quiz if for any reason you can not join the quiz download as pdf and submit after answering and scanning https://quizizz.com/join?gc=72015277 if for any reason you can not join the quiz download here as pdf and submit after answering and scanning K-Chemistry com Chapter 7 Grade 10 SABIS Quiz 20 .pdf Download PDF • 101KB

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4391bc9e-2214-45ba-bfbd-58d86ba4e919 Excess Reagent Summary The reactant that is present in a quantity greater than necessary to react with the limiting reagent.

c2cf4d1c-7109-4960-9a8e-7aed4126da91 Mass Summary A measure of the amount of matter in an object, usually measured in grams or kilograms.

b567f9ed-b3f8-4466-a97e-8b7ebfa59331 Law of Conservation of Matter Summary Matter can never be created or destroyed. It follows that in a chemical reaction mass and atoms are conserved. As a chemical reaction involves a rearrangement of atoms number of molecules is not conserved

330219f5-4bcb-4c01-8d12-1ac180fd5dad Boiling water until it evaporates, then condensing the steam Summary Physical

0e490d9b-81d1-445e-9332-f2c4a92e1894 Sublimation of iodine Summary Endothermic

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b9509307-f4ef-457a-b044-a8b782f7d938 Know that an α particle is the nucleus of a helium atom Summary An α particle, often denoted as ^4He, is a fundamental subatomic particle that serves as the nucleus of a helium atom. It is composed of two protons and two neutrons, giving it a mass number of 4 and an atomic number of 2. The α particle is named after the Greek letter α (alpha) due to its historical significance in early studies of radioactivity and nuclear physics. Being the nucleus of a helium atom means that the α particle carries the essential components responsible for the atom's identity. It contains the positively charged protons, which determine the atomic number and chemical properties of the helium atom. The presence of two protons in the α particle gives it a net positive charge of +2, balancing the negatively charged electrons surrounding the nucleus in a helium atom. The α particle is highly stable due to its tightly bound configuration of protons and neutrons within the nucleus. This stability contributes to its occurrence in various nuclear reactions and natural processes. In certain radioactive decays, such as alpha decay, a parent nucleus emits an α particle, reducing its atomic number by 2 and its mass number by 4. This emission results in the formation of a daughter nucleus with a different atomic identity. The α particle possesses unique properties that distinguish it from other subatomic particles. It has a relatively large mass compared to other particles and can penetrate matter to a limited extent due to its charge and mass. In practical applications, α particles are commonly used in radiation detectors and nuclear research. Their distinctive properties make them useful for studying particle interactions, measuring radiation levels, and investigating the properties of atomic nuclei. Understanding that an α particle is the nucleus of a helium atom is fundamental to comprehending the structure of matter and the behavior of subatomic particles. It allows us to appreciate the role of α particles in nuclear processes and their significance in the overall composition of atoms. In summary, an α particle serves as the nucleus of a helium atom, consisting of two protons and two neutrons. It carries a net positive charge of +2 and possesses unique properties that distinguish it from other subatomic particles. Recognizing the α particle as the nucleus of a helium atom contributes to our understanding of atomic structure, nuclear reactions, and radiation phenomena.

bda04ab2-bab6-4ac7-880b-ec3354adc6c8 Application on Hess’s Law Summary Question 1: Given the following reactions and their respective enthalpy changes: C(graphite) + O2(g) → CO2(g) ΔH1 = -393.5 kJ/mol CO(g) + 1/2O2(g) → CO2(g) ΔH2 = -283.0 kJ/mol C(graphite) + 1/2O2(g) → CO(g) ΔH3 = -110.5 kJ/mol Calculate the enthalpy change for the reaction: C(graphite) + 1/2O2(g) → CO2(g) Answer 1: To calculate the enthalpy change for the given reaction, we can use Hess's Law. By manipulating the given reactions, we can cancel out the common compounds and add the enthalpy changes. Adding reactions 2 and 3 gives: 2CO(g) + O2(g) → 2CO2(g) ΔH2 + ΔH3 = -283.0 kJ/mol + (-110.5 kJ/mol) = -393.5 kJ/mol Since this reaction is the reverse of reaction 1, the enthalpy change for the given reaction is the negative of ΔH1. ΔH = -(-393.5 kJ/mol) = 393.5 kJ/mol Question 2: Given the following reactions and their respective enthalpy changes: N2(g) + O2(g) → 2NO(g) ΔH1 = 180.6 kJ/mol 1/2N2(g) + O2(g) → NO2(g) ΔH2 = 33.2 kJ/mol Calculate the enthalpy change for the reaction: NO(g) + NO2(g) → N2O3(g) Answer 2: To calculate the enthalpy change for the given reaction, we can use Hess's Law. By manipulating the given reactions, we can cancel out the common compounds and add the enthalpy changes. Multiplying reaction 2 by 2 gives: N2(g) + 2O2(g) → 2NO2(g) 2ΔH2 = 2(33.2 kJ/mol) = 66.4 kJ/mol Adding reactions 1 and 2 gives: 2N2(g) + 2O2(g) → 4NO(g) 2ΔH1 + 2ΔH2 = 2(180.6 kJ/mol) + 66.4 kJ/mol = 427.6 kJ/mol Since this reaction is the reverse of the desired reaction, the enthalpy change for the given reaction is the negative of the calculated value. ΔH = -427.6 kJ/mol Question 3: Given the following reactions and their respective enthalpy changes: 2H2(g) + O2(g) → 2H2O(l) ΔH1 = -572 kJ/mol 2H2O(l) → 2H2(g) + O2(g) ΔH2 = 572 kJ/mol Calculate the enthalpy change for the reaction: H2(g) + 1/2O2(g) → H2O(l) Answer 3: To calculate the enthalpy change for the given reaction, we can use Hess's Law. By manipulating the given reactions, we can cancel out the common compounds and add