Answer: She is incorrect to conclude that the reaction is endothermic.
As in the second trial, the temperature has increased by 20 °C , that means the heat has been released and energy is released in exothermic reactions.
Exothermic reactions: The reactions in which the energy of the products is less than the energy of the reactants, and the excess energy is released as heat.
Endothermic reactions: The reactions in which the energy of the products is more than the energy of the reactants, and the excess energy is absorbed as heat.
Answer:
A) reduced air pressure on the ball.
Explanation:
Answer: The correct answer is B
Explanation: The string is pulling right and the string is unraveling causing it to accelerate left
Answer:
The latent heat of vaporization of water is 2.4 kJ/g
Explanation:
The given readings are;
The first (mass) balance reading (of the water) in grams, m₁ = 581 g
The second (mass) balance reading (of the water) in grams, m₂ = 526 g
The first joulemeter reading in kilojoules (kJ), Q₁ = 195 kJ
The second joulemeter reading in kilojoules (kJ), Q₂ = 327 kJ
The latent heat of vaporization = The heat required to evaporate a given mass water at constant temperature
Based on the measurements, we have;
The latent heat of vaporization = ΔQ/Δm
∴ The latent heat of vaporization of water = (327 kJ - 195 kJ)/(581 g - 526 g) = 2.4 kJ/g
The latent heat of vaporization of water = 2.4 kJ/g
<span>D. Convection occurs when heated particles of a material flow toward areas having less thermal energy. This movement of particles can only occur in gases and liquids, not solids.</span>
