Advertisements
Advertisements
प्रश्न
How do you say that the process of digestion is a chemical change ?
उत्तर
During digestion new substances are formed which cannot be converted back to the same food which we have eaten. Besides energy is also released. These factors prove that digestion is a chemical change.
APPEARS IN
संबंधित प्रश्न
Suggest a method to liquefy atmospheric gases.
Give two reasons to justify an iron almirah is a solid at room temperature.
What is the (a) common unit of temperature, and (b) SI unit of temperature ?
What is the name of the process in which a gas turns directly into a solid ?
Fill in the following blank with suitable words :
Scientists say that there are actually five states of matter : solid, liquid, gas, .................... and ...................
Fill in the following blank with suitable words :
The state of matter called ........................ makes a fluorescent tube (or neon sign bulb) to glow.
If the temperature of an object is 268 K, it will be equivalent to :
Which one of the following set of phenomena would increase on raising the temperature ?
On converting 308 K, 329 K and 391 K to Celsius scale, the correct sequence of temperatures will be :
When water is heated to a temperature x, it gets converted into steam at temperature x by a process called R. And when steam at temperature x is cooled, it gets reconverted into water at the same temperature x by a process called S.
- How much is the value of x in Kelvin ?
- What is the process R called ?
- What is the name of the energy absorbed during the process R ?
- What is process S known as ?
- What is the name of energy released during the process S known as ?\\
Define Intermodular force of attraction
Define the following terms: Sublimation
Give reasons:
Why a solid does not flow, but a liquid flows?
State which of the following statement is true or false. If false write the correct statement.
Solids are highly compressible and rigid.
Fill in the blank with the correct word Given below.
Intermingling of molecules is called ____
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.
State whether the following statement is true or false. If false write the correct statement.
During a chemical change the composition of the original substance is not altered and the change is irreversible.
Complete the statement by filling the blank with the correct word given below.
Conversion of vapour [or gas] into a liquid is termed ____________.
Give the reason for the following
On heating a sublimable solid, the molecules break free & escape from the surface of the solid directly into vapour.
Complete the blank with reference to interconversion of matter on the basis of kinetic theory-with the word ‘increase’, ‘decreases’, ‘gain’, ‘lose’, or ‘overcome’ in the following case.
During vaporization, the liquid particles ____________ energy.