What does the flat part of a heating curve indicate?
Heating curves show how the temperature changes as a substance is heated up. Cooling curves are the opposite. They show how the temperature changes as a substance is cooled down. Just like heating curves, cooling curves have horizontal flat parts where the state changes from gas to liquid, or from liquid to solid.
What happens to materials when heated and cooled?
If water is cooled enough, it can change to ice. If ice is warmed enough, it can change to liquid water. Heating a substance makes the molecules move faster. Cooling a substance makes the molecules move slower.
What is the difference between heating curve and phase diagram?
While a heating curve provides information on the phase changes at a single pressure, the phase diagram depicts the phase changes at all temperatures and pressures.
Which phase of water will have the lowest temperature change upon heating when the same amount of heat is applied to each?
liquid
What states of matter are present when the slope of the heating curve is positive and what states of matter are present when the slope is zero or close to zero?
The states of matter that are present when the slope of the heating curve is positive is solid + liquid and liquid + gas. The states of matter that are present when the slope is zero or close to zero are solid, liquid, and gas.
What will happen if we put a glass over a burning candle?
The glass becomes foggy on the inside and the flame fades and eventually goes out. Then the water level in the glass rises. The burning candle produces carbon dioxide and water in the form of water vapor. If the air in the glass cools down and its volume decreases, a negative pressure is created inside the glass.
What happened when salt and water were combined?
When salt is mixed with water, the salt dissolves because the covalent bonds of water are stronger than the ionic bonds in the salt molecules. Water molecules pull the sodium and chloride ions apart, breaking the ionic bond that held them together.
How can you separate the materials in a salt solution?
Answer: Salt can be separated from a solution through evaporation. The water can also be recovered as well as the salt if the water vapor is trapped and cooled to condense the water vapor back into a liquid. This process is called distillation.
What happened when the salt solution was boiled?
When the salt solution was boiled, the particles of salt will remain while the water will evaporate.
Why does the flame shown in the picture extinguishes when a glass jar is put on the burning candle?
Burning of a candle requires oxygen which is present in the air. By covering it with a jar, there is only limited amount of oxygen left in the jar which eventually gets used up. Hence with no more oxygen left, the candle gets extinguished. Thanks!
Why do candle not burn in inverted glass?
As the air in the inverted glass is in contact with water, it will contain saturated vapour. When the candle goes off and the temperature falls, saturation vapour pressure also decreases and some of the vapour condenses. This also decreases pressure inside and helps in rise of water.
Can you light a fire in a glass jar?
Glass jar candles are the best as the glass acts a barrier between the open flame and potentially flammable objects. Plastic furniture can melt when a candle is placed and burning on it for hours on end.
What happens if you light a fire in a Mason jar?
What could happen if you passed an empty glass jar with the lid on tightly into a fire? The glass jar might crack. First, if the lid is plastic or the lid is metal with a plastic liner to make it airtight, then the plastic will melt and allow the air to escape before dangerous pressure can build up in the jar.
Can I burn something in glass?
Glass is mostly SiO2 or “silicon dioxide.” (There are other oxides in glass, depending on the kind: sodium oxide, calcium oxide, etc.) If glass gets really hot it will melt and glow. The “other products” are the things that make the flames. However: Since silicon dioxide is already an oxide, you can’t really burn it.
Is it safe to burn something in glass?
Glass can break if it is subjected to thermal shock. A burning candle is hot, not hot enough to melt glass for certain but if the glass candle holder, heated up by the remnants of the candle, somehow encounters cold liquid it could break and spill the burning wax.