Some Basic Concepts of Chemistry Chemistry Class 11 chapter 1

 Some Basic Concepts of Chemistry Chemistry Class 11 chapter 1 

Chemistry Class 11 chapter 1 Some Basic Concepts of Chemistry 

Topic: - Properties of Matter and their Measurement


1. How are physical properties different from chemical properties?
Physical properties are those properties which can be measured or observed without changing the identity or the composition of the substance whereas the measurement of chemical properties require a chemical change to occur e.g. colour, odour etc are physical properties and combustion, basicity etc are chemical properties


2. What are the two different system of measurement?
The different system of measurement are English system and the metric system.


3. Write seven fundamental quantities & their units.
Physical Quantity                                            SI Unit
1. Length (l)                                                     Metre (m)
2. Mass (m)                                                      Kilogram (kg)
3. Time (t)                                                        Second (s)
4. Electric Current (I)                                      Ampere (A)
5. Thermodynamic Temperature (T)               Kelvin (K)
6. Amount of substance (n)                             Mole (mol)
7. Luminous Intensity (Iν )                              Candela (Cd)


4. What is the difference between mass & weight? How is mass measured in laboratory?
Mass of a substance is the amount of matter present in it while weight is the force exerted by gravity on an object the mass of a substance is determined with the help of an analytical balance in laboratory.


5. How is volume measured in laboratory? Convent 0.5L into ml 
and ?

6. What is the SI unit of density? 

7. What are the reference points in thermometer with Celsius scale? 

The thermometers with Celsius scale are calibrated form 0o to 100o where there two temperatures are the freezing and boiling of water.

8. What is the SI unit of volume? What is the other common unit which in not an SI unit of volume.  

The SI unit of volume is m3 whereas litre (L) is the common unit which is not an SI unit.

9. What does the following prefixes stand for – (a) pico (b) nano (c) centi (d) deci