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Fireworks produce spectacular visual effects due to the interaction of heat, light, and sound generated by chemical reactions. When a firework is ignited, the chemical compounds inside the firework undergo combustion reactions, releasing energy in the form of light (visible as different colors), heat, and sound. The different colors in fireworks are due to the … Read more
Cooking is essential for certain foods due to a variety of reasons, mainly safety, digestibility, and nutrient availability: Killing Harmful Microorganisms: Some raw foods, especially meat, poultry, and eggs, can contain harmful bacteria, viruses, or parasites (e.g., Salmonella, E. coli, or Trichinella). Cooking kills these pathogens, making the food safe to eat. Breaking Down Tough … Read more
Lipids serve several vital functions in the human body: Energy Storage: Lipids, primarily in the form of triglycerides, are the body’s most concentrated source of energy. They are stored in adipose (fat) tissue and can be metabolized to provide energy when needed, especially during periods of fasting or prolonged physical activity. Structural Component of Cells: … Read more
The formation of a bond is always exothermic because when two atoms come together to form a bond, their potential energy decreases. Atoms are naturally attracted to each other due to the electrostatic forces between positively charged nuclei and negatively charged electrons. When atoms form a bond, they move to a lower energy state, which … Read more
Heat (q): Heat refers to the transfer of energy from one body or system to another due to a temperature difference. It is a form of energy in transit. Heat flows from a higher temperature object to a lower temperature object and depends on the mass, specific heat, and temperature difference. Heat is not a … Read more
N2+O2⟶2NO Bond dissociation energy of N₂ = 958.38 kJ/mol Bond dissociation energy of O₂ = 498 kJ/mol Bond formation energy of NO = –626 kJ/mol Solution: To find the enthalpy change (ΔH) of the reaction, we can use the following formula: ΔH=∑(Bond dissociation energies of reactants)−∑(Bond formation energies of products) Bond Dissociation Energies (Reactants): For … Read more
The reaction between methane (CH₄) and oxygen (O₂) is an exothermic combustion reaction, which releases energy in the form of heat and light. The balanced chemical equation for this reaction is: CH4+2O2→CO2+2H2O+energy Under normal conditions, methane and oxygen do not react spontaneously because, like many chemical reactions, this combustion reaction has an activation energy barrier. … Read more
Under normal atmospheric conditions, nitrogen (N₂) and oxygen (O₂) are stable, and the reaction between them does not occur easily. This is because nitrogen has a very strong triple bond between the two nitrogen atoms (N≡N), which requires a significant amount of energy to break. Similarly, oxygen (O₂) is a relatively stable diatomic molecule and … Read more
Glycogen is a polysaccharide that serves as a storage form of glucose in the liver and muscles. It provides a readily available source of energy when blood glucose levels are low, breaking down into glucose when needed for energy production. Related Questions: What is the difference between enthalpy and enthalpy change? Why is breaking of … Read more
In an exothermic reaction, the reaction profile typically shows a decrease in energy from reactants to products. The faster reaction will have a lower activation energy and will reach the product state quicker. Related Questions: What is the difference between enthalpy and enthalpy change? Why is breaking of a bond an endothermic process? Depict the … Read more