<h3>Answers:
</h3><h2>1. (D) 30°C
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A good example that most people are familiar with is the heating of water. If we take a beaker packed with ice (solid water) and put in on a hot plate that has a temperature of 120 ° C we all know what will happen. First, the ice will dissolve to liquid water. Then the water will rise in temperature. Then ultimately the water will boil. During this complete process, the temperature of the hot plate will be greater than the temperature of the beaker of water. Thus, during this whole process energy will move in the form of heat from the hot plate into the water.
<h2>2. (C) Boiling
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When a system comprises only one phase (solid, liquid or gas), the temperature will rise when it gets energy. The rate of temperature rise will be dependent on the heat capacity of the phase in the system. When the heat capacity is high, the temperature rises slowly because much energy is needed to increase its temperature by one degree. Thus, the slope of temperature rise for the solid, liquid, and gases varies.
<h2 /><h2>3. (C) Liquid
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A cooling curve is a line graph that describes the difference of phase of matter, typically from a gas to a solid or a liquid to a solid. The independent variable is time and the dependent variable is temperature. The original point of the graph is the starting temperature of the matter, regarded as the "pouring temperature".
<h2>4. Only the motion and arrangement of the particles changes, not the identity of the substance.</h2>
Water is held together by hydrogen bonds, the soundest of inter-molecular forces. This is where a hydrogen atom in one molecule is completely attracted to an electronegative atom (in this case, oxygen) in the other. When sufficient energy is absorbed by H2O, the molecules vibrate so vigorously that these bonds are loosened, giving them scope to bounce around. When this energy is taken out of the H2O, this transmits room for hydrogen bonds to tighten, squeezing collectively to form a solid.
<h2>5. liquid iron (2,000°C)</h2>
The kinetic energy of an object is the energy that it controls due to its motion. It is described as the work needed to stimulate a body of a given mass from rest to its stated velocity. Having obtained this energy during its acceleration, the body keeps this kinetic energy unless its speed changes.
<h2>6.</h2>
Boiling is the method by which a liquid changes into a vapour when it is burned to its boiling point. The transition from a liquid phase to a gaseous phase happens when the vapour pressure of the liquid is similar to the atmospheric pressure used on the liquid. Boiling is a physical change in which molecules are not chemically altered during the process. When atoms or molecules of a liquid are ready to expand out enough to change from a liquid phase to a gaseous phase, bubbles form and boiling occurs
<h2>7. (C) It will expand because the helium atoms will move more quickly and get farther apart.</h2>
Over a period of centuries and through various experiments, physicists and chemists have been equipped to describe key characteristics of a gas, including the volume it controls (V) and the pressure it exerts on its enclosure (P), to temperature (T).
<h2>8. (C) Neon Gas</h2>
Neon is a colourless, odourless, inert monatomic gas under regular conditions, with about two-thirds the density of air. It was recognized as one of the three residual rare inert elements surviving in the dry air after nitrogen, oxygen, argon and carbon dioxide were evacuated. Neon was the second of these three rare gases to be found and was immediately identified as a new element from its bright red emission spectrum.
