Search Results

Fractional Coefficients Grade 10 SABIS SABIS Coefficients in a chemical equation that are fractions, used to balance the equation.

Application on Hess’s Law Grade 10 SABIS ​ 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

Observations for the reaction of alkali metal with water: Grade 10 SABIS ​  Piece of metal floats (alkali metals have low density).  Piece of metal darts around.  A hissing sound is heard due to the evolution of a gas.  If red litmus paper is dipped in the solution, the paper turns blue due to the formation of the alkali metal hydroxide.  If few drops of phenolphthalein indicator are added to the water solution turns pink due to the formation of alkali metal hydroxide.  If the gas produced is tested with a lit splint, it burns with a squeaky pop sound.

Decomposition Grade 10 SABIS SABIS A chemical reaction in which a single compound breaks down into two or more simpler substances.

Recall the expressions for gravitational potential and kinetic energy of an object Grade 10 SABIS ​ Gravitational Potential Energy: Gravitational potential energy is the energy possessed by an object due to its position in a gravitational field. The expression for gravitational potential energy (PE) is given by the equation: PE = mgh where m represents the mass of the object, g represents the acceleration due to gravity, and h represents the height or vertical distance of the object from a reference point. For example, if we consider a ball of mass m that is lifted to a height h above the ground, the gravitational potential energy of the ball is given by the product of its mass, the acceleration due to gravity, and the height it is lifted to. Kinetic Energy: Kinetic energy is the energy possessed by an object due to its motion. The expression for kinetic energy (KE) is given by the equation: KE = (1/2)mv^2 where m represents the mass of the object and v represents the velocity of the object. If we consider the same ball that was lifted to a height and then released, as it falls downward, its potential energy is converted into kinetic energy. The kinetic energy of the ball is given by half the product of its mass and the square of its velocity. The expression for kinetic energy shows that the kinetic energy of an object is proportional to its mass and the square of its velocity. This means that an object with a larger mass or a higher velocity will possess more kinetic energy. It's important to note that both gravitational potential energy and kinetic energy are scalar quantities, meaning they have magnitude but no specific direction. They are both measured in units of energy, such as joules (J). In summary, the expressions for gravitational potential energy and kinetic energy provide insights into the energy possessed by an object. Gravitational potential energy is determined by the mass of the object, the acceleration due to gravity, and its height from a reference point. Kinetic energy, on the other hand, depends on the mass of the object and its velocity. Understanding these expressions helps us analyze and quantify the energy changes associated with the position and motion of objects in various scenarios.

Atoms or ions that have the same electron arrangement around their nuclei as the noble gases will be stable. Grade 10 SABIS ​

Chemical Change Grade 10 SABIS SABIS Always produces a new kind of matter, is generally not easily reversible, is usually accompanied by considerable heat change, produces no observable change in mass

At RTP and STP, there are two liquid elements: bromine and mercury. Grade 10 SABIS ​

< Back A level Group 2 ​ ​ Previous Next

Know what nuclear reactions is, and that it changes mass to energy Grade 10 SABIS ​ Nuclear reactions involve processes that occur within the atomic nucleus, resulting in changes in the composition of atomic nuclei. These reactions can involve the transformation of one nucleus into another through processes such as nuclear fission or nuclear fusion. In nuclear reactions, the nucleus of an atom undergoes changes, typically by gaining or losing subatomic particles, such as protons or neutrons. These changes can lead to the formation of new isotopes or elements, accompanied by the release or absorption of a tremendous amount of energy. One of the fundamental concepts in nuclear reactions is the relationship between mass and energy. According to Einstein's famous equation, E = mc^2, energy (E) is equivalent to mass (m) multiplied by the speed of light squared (c^2). This equation demonstrates that mass and energy are interconvertible and can be transformed from one form to another. During nuclear reactions, a tiny fraction of the mass of the participating particles is converted into a significant amount of energy. This conversion occurs due to the difference in the total mass of the reactants and products before and after the reaction. In processes like nuclear fission, the splitting of a heavy nucleus into two or more lighter nuclei results in a slight decrease in total mass. This lost mass is converted into an enormous amount of energy, as dictated by Einstein's equation. Conversely, in nuclear fusion reactions, the combination of two light nuclei to form a heavier nucleus results in a slight increase in total mass. This increase in mass is compensated by the release of a substantial amount of energy. The conversion of mass to energy in nuclear reactions is governed by the principle of mass-energy equivalence. It highlights the tremendous energy potential contained within the nucleus of an atom, far exceeding the energy released in chemical reactions. The release of energy in nuclear reactions has significant implications in various fields, including nuclear power generation, nuclear weapons, and scientific research. Understanding the principles of nuclear reactions and the mass-energy relationship is crucial for harnessing nuclear energy responsibly and for advancing our understanding of the universe. It's important to note that nuclear reactions involve highly energetic and complex processes, requiring specialized knowledge and precautions to ensure safety and proper handling. These reactions are primarily studied and utilized in controlled environments by experts in the field. In summary, nuclear reactions involve changes that occur within the atomic nucleus, resulting in the transformation of one nucleus into another. These reactions demonstrate the interconversion of mass and energy, with a small fraction of mass being transformed into a substantial amount of energy. Understanding nuclear reactions and their ability to change mass to energy is essential in various scientific, technological, and energy-related applications.

< Back Chapter 9: Bonding in Solids and Liquids Discover the different types of bonding present in solids and liquids and how they affect the physical and chemical properties of materials. Chapter 9: Bonding in Solids and Liquids - This chapter covers the different types of bonding in solids and liquids. Students will learn about metallic bonding, ionic bonding, and covalent bonding. The chapter also covers the properties of solids and liquids, including viscosity and surface tension. Previous Next

Melting/Fusion ​ ​ The change of a substance from a solid to a liquid state at a specific temperature.