Answer:
Explanation:
<em>Endothermi</em>c processes absorb energy. The final state contains more energy than the initial state.
Since ice absorbs heat energy <em>in the process of completely melting</em> this is an <em>endothermic</em> process.
The process involves two stages: 1) heating the ice up to the melting point, which is 0ºC, and 2) melting the ice.
1. Heating the ice from -15ºC to 0ºC
a) Formula: Q = m×C×ΔT
- C = 2.108 kJ/kg.ºC (specific heat of ice)
b) Calculations:
- Q = m×C×ΔT = 1.6 kg × 2.108 kJ/kg.ºC × 15ºC = 50.592 kJ
2. Melting the ice at 0ºC
a) Formula: L = m × ΔHf
- ΔHf = 334 kJ/kg (latent heat of fussion)
b) Calculations
- L = m × ΔHf = 1.6 kg × 334 kJ/kg = 534.40 kJ
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<u>2. Total heat</u>
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- 50.592 kJ + 534.40 kJ = 584.992 kJ ≈ 590 kJ (rounded to 2 significant figures)
Answer:
the answer is a.cut off the supply of oxygen
Heat will go from hot coffee to the cold cream and vise versa
The answer is Equivalence point. When the condition of [H+] = [OH-<span>] is reached, this state is called the </span><span>equivalence point.</span>
Answer:
This question is incomplete, the remaining part of the question is:
What is the control group, independent variable and dependent variable?
Control group: Plants placed in 80 degree rooms
Independent variable: Change in temperature
Dependent variable: Change in color of leaves
Explanation:
The independent variable in a scientific experiment is the variable that the experimenter controls or manipulates in order to bring about a change in the dependent variable. In this experiment, the variable manipulated by Justin B is the TEMPERATURE CHANGE.
On the other hand, a variable is said to be dependent if it is the variable that responds to a change made to the independent variable or rather it is the outcome. In this experiment, Justin B is trying to see the outcome on the color change in leaves when exposed to a low temperature, hence, COLOR CHANGE IN LEAVES is the dependent variable.
Control group of an experiment is the group that receives no experimental treatment. It is the group the experimenter considers normal and hence is comparing with his experimental group. In this experiment, Justin B believes the leaves change color in a low temperature, hence, he placed some plants in a lower temperature (60 degree) in order to compare them with when the plants are placed in a higher temperature (80 degree). As far as this experiment is concerned, the plants placed in 80 degrees temperature are believed by Justin B not to undergo color change, hence, they are the CONTROL GROUP while the group he placed in 60 degrees temperature are what he is interested in, making them the EXPERIMENTAL GROUP
