Advertisements
Advertisements
Question
What do you observe when :
water is boiled
Solution
On boiling water changes into steam (gas) physical change.
APPEARS IN
RELATED QUESTIONS
For any substance, why does the temperature remain constant during the change of state?
What is the physical state of water at 25°C.
Is there any change in temperature during the change of phase?
The Kelvin temperature is 270 K. What is the corresponding Celsius scale temperature ?
What is the common name of solid carbon dioxide ?
Under what conditions heat can be given to a substance without raising its temperature ?
Which contains more heat, 1 kg of water at 100° C or 1 kg of steam at 100° C ? Give reason for your answer.
Why does the temperature of a substance remain constant during the change of state ?
Which of the following factors are responsible for the change in state of solid carbon dioxide when kept exposed to air ?
- increase in pressure
- ncrease in temperature
- decrease in pressure
- decrease in temperature
There are four substances W, X, Y and Z. The substance W is a dark violet solid having diatomic molecules. A solution of W in alcohol is used as a common antiseptic C. The substance X is a white solid which is usually recovered from sea water on a large scale. The substance Y is a white solid which is insoluble in water and used in the form of small balls for the safe storage of woollen clothes. The substance Z is a yet another white solid which is used in making commonly used dry cells.
- Name (i) W (ii) X (iii) Y and (iv) Z.
- Out of W, X, Y and Z, which substance/substances can undergo sublimation ?
- Which substance is organic in nature ?
- What is the name of substance C ?
- Which substance belongs to the halogen family ?
When water is cooled to a temperature x, it gets converted into ice at temperature x by a process called P. And when ice at temperature x is warmed, it gets reconverted into water at the same temperature x in a process called Q.
- What is the value of temperature x in Kelvin ?
- What is the process P known as ?
- What is the name of energy released during process P ?
- What is the process Q known as ?
- What is the name of energy absorbed during process Q ?
Give reasons:
How is interconversion of states of matter different from chemical reaction?
Write whether the following statement is true or false:
The intermolecular force of attraction is the weakest in gases.
Name the phenomenon which causes the following changes:
Formation of water vapour from water
Give two examples of the following:
Substances which sublime.
In the paragraph below, write ‘solid’, ‘liquid’ or ‘gas’ in each of the brackets depending on the substance referred to just before.
On a bright sunny day, Riya and Gargi are playing with a ball ( ) in the park. Gargi feels thirsty. So, Riya brings tender coconut water ( ) for her. At the same time, a strong breeze ( ) starts blowing and it also begins to rain ( ). They run back into the house ( ), change their clothes ( ), and then their mother gives them a cup ( ) of hot milk ( ) to drink.
Why does this happen?
Kerosene left open in a dish disappears.
Matter in any state is composed of small particles – molecules, atoms, or ions. Differentiate the terms above in Italics.
With reference to the liquid state of matter – answer the following
The heat energy supplied to the liquid is absorbed by its molecule & stored as which form of energy.
