Answer :

(a) Atomic mass- Atomic mass is defined as the sum of a number of protons and neutrons normally found in the nucleus of an atom of a given element. It is measured in u (unified mass) or amu (atomic mass unit).


Ex-The atomic mass of Oxygen (O) is 16. It is the sum of 8 protons and 8 neutrons present in its nucleus.


(b) Relative atomic mass- Relative atomic mass (Ar) is a dimensionless quantity. It is defined as the ratio of the average mass of atoms of an element of a given sample to the 1/12 of the atomic mass of a carbon-12 atom.


Ex- Relative atomic mass of Aluminium (Al)


=


=


=


= 26.98 u


(c) Gram molecular mass- Gram molecular mass of a substance is its relative molecular mass expressed in grams.


Ex- Gram molecular mass of Aluminium (Al) = 26.98g


(d) Mole- A mole of a substance is defined as the amount of substance containing a same number of atoms or molecules as there are atoms in exactly 12g of carbon-12.


(e) Valency of an element- Valency is the combining capacity of an element. It is the number of electrons an atom of an element can gain or loss.


If valence electrons are 4 or less then the valency of an atom is equal to the valence electrons. And if valence electrons are more than 4, the valency is equal to 8 minus the number of electrons in the outer most shell.


Ex- Sodium has electronic configuration 2, 8, 1. So its valency is 1 because it has 1 valence electrons. Oxygen has electronic configuration 2, 6. So its valency is 2 because it has 6 valence electrons.


Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Quiz on Friction + ForceQuiz on Friction + ForceQuiz on Friction + Force30 mins
Champ Quiz | Force, Pressure & SoundChamp Quiz | Force, Pressure & SoundChamp Quiz | Force, Pressure & Sound29 mins
Quiz | Powers and ExponenntsQuiz | Powers and ExponenntsQuiz | Powers and Exponennts43 mins
Goprep Genius Quiz | Squares and Square RootsGoprep Genius Quiz | Squares and Square RootsGoprep Genius Quiz | Squares and Square Roots34 mins
Motion and TimeMotion and TimeMotion and Time38 mins
Goprep Genius Quiz on Direct and Inverse proportionsGoprep Genius Quiz on Direct and Inverse proportionsGoprep Genius Quiz on Direct and Inverse proportions32 mins
Ratio and PercentageRatio and PercentageRatio and Percentage34 mins
Genius Quiz | How, When and WhereGenius Quiz | How, When and WhereGenius Quiz | How, When and Where38 mins
QUIZ | Exponents and PowerQUIZ | Exponents and PowerQUIZ | Exponents and Power35 mins
NCERT | Combustion and FlameNCERT | Combustion and FlameNCERT | Combustion and Flame35 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
caricature
view all courses
RELATED QUESTIONS :

Give a scientificKarnataka Board - Science Part I

Give a scientificKarnataka Board - Science Part I

Some elements canKarnataka Board - Science Part I

Answer the followKarnataka Board - Science Part I