First of all, energy and temperature is different. In an exothermic reaction, chemical potential energy is converted to thermal energy. So the total energy stored (chemical potential energy) is released, but total thermal energy (temperature) increases.
For example, a burning coal is hotter than a coal, right?
Q29. As there is no air resistance, only gravitational acceleration affects an object. Like its name, it's an acceleration. This is constant as gravitational acceleration is a constant value (9.8). So A.
Q30. Centre of mass and base area affects stability. Z has largest base area and lowest centre of mass, so it has highest stability. Also, Y and X have similar base area, but Y has lower centre of mass, so Y is more stable than X. So it would be Z>Y>X. So D.
Q17. When its exothermic, energy is given out and temperature increases. As temperature increases, the reaction must be exothermic. So B.
Ok, thank you.
First of all, energy and temperature is different. In an exothermic reaction, chemical potential energy is converted to thermal energy. So the total energy stored (chemical potential energy) is released, but total thermal energy (temperature) increases.
For example, a burning coal is hotter than a coal, right?
Ok, but I'm still quite confused about the exothermic one. Exothermic reactions release energy, so won't temperature decrease?
Hi, thank you for your question.
Q29. As there is no air resistance, only gravitational acceleration affects an object. Like its name, it's an acceleration. This is constant as gravitational acceleration is a constant value (9.8). So A.
Q30. Centre of mass and base area affects stability. Z has largest base area and lowest centre of mass, so it has highest stability. Also, Y and X have similar base area, but Y has lower centre of mass, so Y is more stable than X. So it would be Z>Y>X. So D.
Q17. When its exothermic, energy is given out and temperature increases. As temperature increases, the reaction must be exothermic. So B.