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- Evaporation
Evaporation โ โ The process of a substance changing from a liquid to a gaseous state at a specific temperature.
- Reading Equations
Reading Equations Grade 10 SABIS SABIS Using masses of reactants and products
- Atomicity explanation
Atomicity explanation General โ Lesson: Atomicity ๐ฌ Introduction: In chemistry, atomicity refers to the number of atoms present in a molecule. It tells us how many atoms of an element are bonded together to form a single unit of a compound. Understanding atomicity is crucial in determining the properties and behavior of substances at the atomic level. Let's explore the concept of atomicity in more detail. ๐ก Definition of Atomicity: Atomicity is the term used to describe the number of atoms bonded together within a molecule. It represents the smallest unit of a compound that retains the chemical properties of that substance. ๐ Examples of Atomicity: Oxygen (O2): Oxygen gas consists of two oxygen atoms bonded together. This means the atomicity of oxygen gas is 2, indicating that two oxygen atoms are chemically bonded within each oxygen molecule. Ozone (O3): Ozone is a molecule composed of three oxygen atoms bonded together. The atomicity of ozone is 3, signifying that three oxygen atoms form each ozone molecule. Hydrogen (H2): Hydrogen gas consists of two hydrogen atoms bonded together, giving it an atomicity of 2. ๐ฌ Determining Atomicity: To determine the atomicity of a molecule, we examine its chemical formula and identify the number of atoms of each element present. The subscript numbers in the formula represent the atomicity. ๐ฅ Significance of Atomicity: Atomicity plays a significant role in understanding the physical and chemical properties of substances. It influences factors such as reactivity, stability, and bonding behavior. ๐งช Quiz (Basic Understanding): What does atomicity refer to? a) The number of atoms bonded together within a molecule. b) The mass of an atom. c) The atomic number of an element. What is the atomicity of oxygen gas (O2)? a) 1 b) 2 c) 3 How many atoms are bonded together in a water molecule (H2O)? a) 1 b) 2 c) 3 What does the atomicity of a compound determine? a) Its color b) Its physical state c) The number of atoms in a molecule What is the atomicity of hydrogen gas (H2)? a) 1 b) 2 c) 3 ๐ Answers: a) The number of atoms bonded together within a molecule. b) 2 b) 2 c) The number of atoms in a molecule b) 2 Great job! You've gained a basic understanding of atomicity and its significance in chemistry. Keep exploring the world of atoms and molecules to deepen your knowledge in this exciting field!
- Conservation of Mass
Conservation of Mass Grade 10 SABIS SABIS In chemical reactions, the total mass of the reactants is equal to the total mass of the products. This principle states that matter cannot be created or destroyed.
- Atomic Structure Lesson 3
< Back Atomic Structure Lesson 3 โ๏ธ Lesson 3 โ๏ธ This section explores the subatomic structure of atoms and ions, highlighting the role of protons as unchanging identifiers of elements and the flexible nature of electrons in forming ions. The calculation of protons, neutrons, and electrons in an unknown element is demonstrated, unveiling the subatomic structure and identity of the element. Understanding these concepts allows us to uncover the hidden structure of the universe, atom by atom. Previous Next โ๏ธ 1.1.3 Determining Subatomic Structure โ๏ธ ๐ฅ๐ฌ Cracking the Code of Subatomic Structures: Protons, Electrons, and Neutrons ๐ฌ๐ฅ โ๏ธ Atoms & Ions: A Tale of Charges โ๏ธ Imagine an atom as a tiny city, bustling with life and balance. At its heart, it's neutralโlike a well-managed city where everyone has a role to play. But sometimes, atoms get adventurous! They might lose or gain citizens (electrons), leading to charged cities we call ions. โก๐ ๐ซ Protons: The Unchanging Pillars of Atomic Identity ๐ซ The number of protons is like the DNA of an atomโit doesn't change and identifies the element. Be it the lithium city with 3 protons or the beryllium city with 4, every atom and ion of the same element shares the same proton number (atomic number). So, how do we count these unchanging pillars (protons) in an unknown element? With some simple math! ๐งฎ๐ Mass number = number of protons + number of neutrons Number of protons = mass number - number of neutrons ๐ก E.g., for an unknown element X with a mass number of 63 and 34 neutrons: Number of protons = 63 - 34 = 29 ๐ We just revealed the identity of element Xโit's copper! ๐ฅณ๐ ๐จ Electrons: The Flexible Players ๐จ While protons are the steadfast pillars, electrons are more flexibleโthey may change in ions. In a neutral atom, the number of electrons equals the number of protons. But ions dance to a different tune: positively charged ions (cations) have fewer electrons, and negatively charged ions (anions) have more! ๐ถ๐ For our mystery element X: Number of protons (and electrons in a neutral atom) = 29 ๐ฏ โ๏ธ Neutrons: The Balancing Act โ๏ธ And finally, let's not forget the neutrons. They don't carry any charge but contribute to the mass. We can find their number with another bit of math: Number of neutrons = mass number - number of protons ๐ E.g., for our element X with a mass number of 63 and 29 protons: Number of neutrons = 63 - 29 = 34 ๐ Just like that, we've unveiled the full subatomic structure of element XโCopper with 29 protons, 29 electrons, and 34 neutrons! ๐๐ฌ By understanding these concepts, you're not just learning chemistryโyou're uncovering the unseen structure of the universe, one atom at a time! ๐ฅ๐ What can atoms become when they gain or lose electrons? A) Ions ๐ B) Neutrons ๐งช C) Protons โก D) Isotopes ๐ฌ The number of __________ determines the identity of an element. A) Electrons ๐ซ B) Protons โ๏ธ C) Neutrons โก D) Isotopes ๐ How can we calculate the number of protons in an unknown element? A) Mass number + number of neutrons ๐งฎ B) Mass number - number of neutrons ๐ C) Number of neutrons + number of electrons ๐ D) Number of electrons - number of neutrons ๐ก What is the charge of a neutral atom? A) Positive โก B) Negative ๐ฅ C) Neutral ๐ D) Variable ๐ What happens to the number of electrons in ions? A) They remain the same as in neutral atoms. ๐ B) They decrease in cations and increase in anions. โฌ๏ธโฌ๏ธ C) They increase in cations and decrease in anions. โฌ๏ธโฌ๏ธ D) They become neutral. โ๏ธ In a neutral atom, the number of electrons is equal to the number of __________. A) Protons ๐ B) Neutrons ๐ C) Ions โ๏ธ D) Isotopes ๐ฌ Which subatomic particles contribute to the mass of an atom? A) Protons and electrons ๐ฅ๐ซ B) Protons and neutrons ๐งชโ๏ธ C) Electrons and neutrons โก๐ D) Protons, electrons, and neutrons ๐ฌ๐ฅ๐ซ How can we calculate the number of neutrons in an atom? A) Mass number - number of protons ๐งฎ B) Mass number + number of protons ๐ C) Number of protons - number of electrons ๐ D) Number of protons + number of electrons ๐ก Copper has an atomic number of 29. How many protons does a copper atom have? A) 29 ๐ B) 63 ๐ฌ C) 34 ๐งช D) 0 ๐ฅ An element has a mass number of 47 and 20 neutrons. How many protons does it have? A) 20 ๐ B) 27 โ๏ธ C) 47 ๐งช D) 67 ๐ Keep up the great work in unraveling the mysteries of subatomic structures and their impact on determining the identity of elements! Let your vibrant and creative knowledge shine brightly! ๐๐ฌ๐ซ
- Charge and number of nucleons are conserved in nuclear reactions
Charge and number of nucleons are conserved in nuclear reactions Grade 10 SABIS โ In nuclear reactions, such as nuclear fission and nuclear fusion, two fundamental principles known as charge conservation and conservation of number of nucleons come into play. These principles state that the total electric charge and the total number of nucleons (protons and neutrons) are conserved during nuclear reactions. Charge conservation refers to the principle that the total electric charge of the reactants must equal the total electric charge of the products in a nuclear reaction. This means that the positive charge carried by protons and the neutral charge carried by neutrons must be balanced on both sides of the reaction equation. For example, in a nuclear reaction involving the decay of a radioactive nucleus, if the reactant nucleus has a certain number of protons, the total number of protons in the product nucleus must be the same to ensure charge conservation. Conservation of the number of nucleons refers to the principle that the total number of nucleons (protons and neutrons) in the reactants must equal the total number of nucleons in the products. This conservation principle ensures that the total mass and overall nuclear composition remain constant during the reaction. For instance, in a nuclear fission reaction where a heavy nucleus splits into two smaller nuclei, the total number of protons and neutrons in the reactant nucleus must be equal to the sum of the protons and neutrons in the product nuclei to conserve the number of nucleons. These conservation principles are a consequence of the strong nuclear force that binds protons and neutrons in the atomic nucleus. This force maintains the stability and structure of the nucleus and governs the interactions during nuclear reactions. The conservation of charge and number of nucleons plays a crucial role in understanding and predicting the outcomes of nuclear reactions. It allows scientists to balance nuclear equations, determine the identities of the products, and ensure that fundamental physical laws, such as conservation of mass and charge, are obeyed. It's important to note that while charge and number of nucleons are conserved overall, individual protons and neutrons may change their positions or states within the reactants and products. However, the total number and charge of these particles remain constant. By conserving charge and number of nucleons in nuclear reactions, scientists can analyze the behavior of atomic nuclei, study the energy transformations involved, and explore the potential applications of nuclear processes, such as in power generation or medical diagnostics. In summary, charge conservation and conservation of the number of nucleons are fundamental principles in nuclear reactions. These principles ensure that the total electric charge and the total number of nucleons remain constant before and after the reaction. By obeying these conservation laws, scientists can analyze and understand the behavior of atomic nuclei and the energy transformations that occur in nuclear reactions.
- 11. Vaporization of ethanol Endothermic
11. Vaporization of ethanol Endothermic Grade 10 SABIS SABIS
- Atomic Structure Lesson 6
< Back Atomic Structure Lesson 6 โ๏ธ Lesson 6 โ๏ธ This quiz tests your knowledge of atomic structure, radii, and isotopes. Answer multiple-choice and fill-in-the-blank questions to demonstrate your understanding of these concepts and their significance in the world of chemistry. Good luck! ๐งช๐ฌ Previous Next โ๏ธSmall Quiz Lesson 6โ๏ธ ๐ฑ 1. What is the smallest part of an element that can participate in chemical reactions? ๐ค a) Neutron b) โ๏ธ Proton c) โก๏ธ Electron d) ๐ฌ Isotope ๐ 2. Where are protons and neutrons found in an atom? ๐ a) In the ๐ nucleus b) In the electron cloud โ๏ธ c) In the orbitals ๐ d) In the shells ๐ โก๏ธ 3. What is the charge of an electron? โก๏ธ a) Positive โ b) Negative โ c) Neutral โ๏ธ d) Variable ๐ ๐ญ 4. What do we call the particles that an atom is made up of? ๐ญ a) Electrons ๐ซ b) Protons โ๏ธ c) Neutrons ๐ d) Isotopes ๐ฌ Fill in the Blanks: ๐ซ 5. Electrons have __________ mass compared to protons and neutrons. Answer: ๐ Negligible/lightweight ๐ 6. In a neutral atom, the number of electrons is equal to the number of __________. Answer: โ๏ธ Protons ๐ 7. When it comes to chemical properties, isotopes of the same element exhibit strikingly similar behaviors due to the identical number of __________ in their outer shells. Answer: Electrons ๐ 8. The atomic radius is half the distance between the nuclei of two bonded atoms and measures the __________ of an atom. Answer: Size ๐งฉ 9. Atomic radii generally decrease as you move across each Period of the Periodic Table due to the increasing number of __________. Answer: Protons ๐ 10. If an atom loses electrons to become a positively charged ion (cation), its ionic radius __________. Answer: Decreases Keep up the great work with your learning journey! ๐๐ฌ๐ก Multiple Choice Questions: ๐ 11. What creates an electric field that influences the movement of charged particles? a) ๐งฒ Magnetic fields b) ๐ช๏ธ Gravitational fields c) ๐ Charged plates d) ๐ Rainbow fields ๐ฌ 12. What determines the identity of an element? a) Atomic mass b) Number of electrons c) Atomic number d) Number of neutrons ๐ช 13. What is the role of electrons in chemical reactions? a) Stabilizing the nucleus b) Determining the mass of the atom c) Participating in bonding d) Influencing the atomic radius ๐ 14. What happens to the charge of an atom if it loses an electron? a) Becomes positively charged b) Becomes negatively charged c) Remains neutral d) Varies depending on the atom ๐ 15. What are the charges of protons, neutrons, and electrons, respectively? a) +1, -1, 0 b) 0, +1, -1 c) +1, 0, -1 d) -1, 0, +1 Fill in the Blanks: โ๏ธ 16. The number of neutrons in an atom can be calculated by subtracting the atomic number from the __________. Answer: Mass number ๐ 17. In an electric field, electrons are deflected __________ from the negative plate and toward the positive plate. Answer: ๐ช๏ธ Away ๐งช 18. An element has a mass number of 63 and 29 protons. The number of neutrons in this element is __________. Answer: 34 ๐ 19. The atomic number determines the position of an element in the __________. Answer: Periodic table ๐ 20. Ions are formed when atoms gain or lose __________. Answer: Electrons ๐ 21. Neutrons remain __________ by the charged plates in an electric field due to their neutral nature. Answer: ๐ Unaffected โ๏ธ 22. Copper has an atomic number of 29. How many protons does a copper atom have? Answer: 29 ๐ 23. What do we call the particles that an atom is made up of? Answer: Subatomic particles ๐ 24. The electron's movement in an electric field showcases its __________ charge and small mass. Answer: ๐ซ Negative ๐ฅ 25. The number of protons (and electrons in a neutral atom) in an element with atomic number 17 is __________. Answer: 17 Great job so far! Keep up the momentum and continue exploring the fascinating world of atoms and their structures! ๐๐ญ Multiple Choice Questions: โ๏ธ 26. What determines the identity of an element? a) Atomic radius b) Number of neutrons c) Mass number d) Atomic number ๐ 27. How does the arrangement of electrons impact the chemical properties of an atom? a) It determines the atomic mass. b) It affects the atomic radius. c) It determines the number of protons. d) It influences bonding and reactivity. ๐ 28. What is the term for protons and neutrons together? a) Nucleons b) Ions c) Isotopes d) Electrons ๐ก 29. How can we calculate the number of neutrons in an atom? a) By subtracting the mass number from the atomic number. b) By adding the atomic number to the mass number. c) By subtracting the number of protons from the mass number. d) By adding the number of protons to the atomic number. โก 30. What is the space called that electrons move around in, outside the nucleus? a) Electron cloud b) Orbital c) Nucleus d) Valence shell Fill in the Blanks: ๐ 31. The atomic number tells us the number of __________ in the nucleus of an atom. Answer: Protons โ๏ธ 32. If an atom gains an electron, it becomes __________ charged because electrons carry a negative charge. Answer: Negatively ๐ช 33. The number of __________ determines the position of an element in the periodic table. Answer: Protons (atomic number) ๐ฌ 34. The number of neutrons in an atom can be calculated by subtracting the __________ from the mass number. Answer: Atomic number ๐ซ 35. Electrons have __________ mass compared to protons and neutrons. Answer: Negligible/lightweight ๐ 36. The atomic radius is half the distance between the nuclei of two __________ atoms bonded together. Answer: Identical/same โ๏ธ 37. In a neutral atom, the number of electrons is equal to the number of __________. Answer: Protons ๐ 38. What is the charge of a neutral atom? Answer: Neutral/zero/0 ๐ญ 39. Neutrons contribute to the __________ of an atom without affecting its charge. Answer: Mass ๐ 40. Atoms get adventurous and become charged cities called __________. Answer: Ions Fantastic progress! You're doing a great job exploring the intricate details of atomic structure. Let's continue uncovering more about atoms, their properties, and their behavior! ๐งช๐ Multiple Choice Questions: ๐ 41. What resides in the nucleus and holds nearly all of the atom's mass? a) Electrons b) Neutrons c) Protons d) Isotopes ๐ 42. What creates an electric field that influences the movement of charged particles? a) Atomic radius b) Neutrons c) Protons d) Charged plates ๐ 43. What causes the atomic radius to decrease as you travel across each Period in the periodic table? a) Increasing number of protons b) Increasing number of neutrons c) Increasing number of electrons d) Increasing number of shells โก 44. If an atom loses electrons to become a positively charged ion, what happens to its ionic radius? a) It increases b) It decreases c) It remains the same d) It becomes neutral ๐ฏ 45. What do isotopes of the same element share? a) Same number of protons and electrons b) Same number of neutrons and electrons c) Same number of protons and neutrons d) Same atomic mass Fill in the Blanks: ๐ฅ 46. The atomic radius generally __________ as you travel down each Group in the periodic table. Answer: Increases/grows/get larger ๐ 47. Atomic radii generally __________ as you travel across each Period in the periodic table. Answer: Decrease/get smaller ๐ 48. An atom becomes a positively charged ion (cation) when it loses __________. Answer: Electrons ๐ 49. An atom becomes a negatively charged ion (anion) when it gains __________. Answer: Electrons ๐บ๏ธ 50. Atomic and ionic radii offer a sort of "map" to the __________ of atoms and ions. Answer: Universe/microcosm/realm Well done! You're making great progress in understanding atomic structure, radii, and the behavior of atoms and ions. Keep up the fantastic work, and let's continue exploring the fascinating world of chemistry together! ๐๐งช๐
- Chapter 9 Prerequisite
< Back Chapter 9 Prerequisite โ โ Previous Next ๐๐ Prerequisites for Chapter 9: Rate of Reaction ๐๐Before diving into Chapter 9, which deals with the rate of reaction, students must have a solid understanding of the following concepts:๐ฌ 1. Basic Chemistry Concepts ๐งชUnderstand atoms, molecules, ions, and chemical reactions.๐ฌ 2. Collision Theory ๐ฅUnderstand that reactions occur when particles collide with sufficient energy and proper orientation.๐ฌ 3. Activation Energy ๐Understand the concept of activation energy as the minimum energy required for a reaction to occur.๐ฌ 4. Factors Affecting Reaction Rates ๐Understand how temperature, concentration, surface area, and catalysts affect reaction rates.๐ 20 Multiple Choice Questions for Chapter 9: Rate of Reaction ๐What is the term for how fast reactants are consumed or products are formed in a chemical reaction? a) Reaction rate b) Activation energy c) Equilibrium constant d) EnthalpyAccording to collision theory, what must occur for a reaction to take place? a) Particles must collide with sufficient energy and proper orientation. b) Particles must collide with low energy. c) Particles must avoid colliding. d) Particles must collide with any orientation.What is the term for the minimum energy that reacting particles must have to form the activated complex? a) Reaction rate b) Activation energy c) Equilibrium constant d) EnthalpyHow does increasing the temperature affect the rate of a chemical reaction? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.How does increasing the concentration of reactants affect the rate of a chemical reaction? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.What is the term for a substance that increases the rate of a reaction without being consumed? a) Inhibitor b) Catalyst c) Solvent d) ReactantHow does increasing the surface area of a solid reactant affect the rate of a chemical reaction? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.What is the term for the highest point on the reaction path where bonds are breaking and new bonds are forming? a) Activated complex b) Transition state c) Reaction intermediate d) Both a and bHow does adding a catalyst affect the activation energy of a reaction? a) Increases activation energy. b) Decreases activation energy. c) Does not affect activation energy. d) Destroys activation energy.What is the effect of a catalyst on the rate of a reaction? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.In the rate expression rate = k[A][B], what does k represent? a) Rate of reaction b) Activation energy c) Rate constant d) Concentration of reactantsHow does increasing the pressure affect the rate of a reaction involving gases? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.What is the term for a graph that shows the change in concentration of reactants or products over time? a) Reaction coordinate diagram b) Reaction rate graph c) Concentration-time graph d) Activation energy graphWhat is the term for a short-lived, high-energy arrangement of atoms during a chemical reaction? a) Activated complex b) Transition state c) Reaction intermediate d) CatalystHow does the presence of a catalyst affect the position of equilibrium in a reaction? a) Shifts it to the right. b) Shifts it to the left. c) Does not change the position. d) Destroys the equilibrium.What is the term for the number of collisions per second between the reactant molecules? a) Collision frequency b) Reaction rate c) Activation energy d) Rate constantWhat is the effect of an inhibitor on the rate of a reaction? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.In the reaction A -> B, if the concentration of A decreases linearly over time, what is the order of the reaction? a) Zero order b) First order c) Second order d) Third orderWhat is the term for a substance that slows down the rate of a chemical reaction? a) Inhibitor b) Catalyst c) Solvent d) ReactantIn a first-order reaction, how does the rate of reaction depend on the concentration of the reactant? a) Rate is proportional to the square of the concentration. b) Rate is inversely proportional to the concentration. c) Rate is proportional to the concentration. d) Rate is independent of the concentration.๐ Answers ๐a) Reaction ratea) Particles must collide with sufficient energy and proper orientation.b) Activation energya) Increases the rate.a) Increases the rate.b) Catalysta) Increases the rate.d) Both a and bb) Decreases activation energy.a) Increases the rate.c) Rate constanta) Increases the rate.c) Concentration-time grapha) Activated complexc) Does not change the position.a) Collision frequencyb) Decreases the rate.b) First ordera) Inhibitorc) Rate is proportional to the concentration.
- Atoms Elements and Compounds
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- A level Hydroxy compounds
< Back A level Hydroxy compounds โ โ Previous Next
- Generally, reactions with low activation energy tend to be fast
Generally, reactions with low activation energy tend to be fast Grade 10 SABIS โ