ELECTROPOSITIVE CHARACTER

Standard electrode potential values, E^(theta) for Al^(3+)// Al is - 1.66 V and that of Tl^(3+)// Tl is + 1.26 V. Predict about the formation of M^(3+) ion in solution and compare the electropositive.character of the two metals.

(a) Standard electrode potential value E^@ for Al^(3+)//Al is - 1.66 V and that of Tl^(3+)//Tl is + 1.26 V . Predict about the formation of M^(3+) ion in solution and compare the electropositive character of the two metals. (b) White fumes appear around the bottle of anhydrous aluminium chloride. Give reason. ( c) Boron is unable to form BF_(6)^(3-) ion. Explain.

The atomic numbers of five elements A, B, C, D and E are 6, 8, 3, 7 and 9 respectively. (i) Which is the element having the highest electropositivity among these elements ? Why? (ii) Which is the element having the least metallic character among these elements ? Why? (iii) What is your conclusion about the relationship between metallic character and electropositivity of an element ?

Metallic Character The ability of an atom to donate electrons and form positive ion (cation) is known as electropositivity or metallic character. Down the group, metallic character increases due to increase in atomic size and across the period, from left to right electropositivity decreases due to decrease in atomic size. Non-Metallic Character The ability of an atom to accept electrons to form a negative ion (anion) is called non-metallic character or electronegativity. The elements having high electro-negativity have a higher tendency to gain electrons and form anion.Down the group, electronegativity decreases due to increase in atomic size and across the period, from left to right electronegativity increases due to decrease in atomic size Hydrogen is placed along with Alkali metals in the modern periodic table though it shows non-metallic character

Metallic Character The ability of an atom to donate electrons and form positive ion (cation) is known as electropositivity or metallic character. Down the group, metallic character increases due to increase in atomic size and across the period, from left to right electropositivity decreases due to decrease in atomic size. Non-Metallic Character The ability of an atom to accept electrons to form a negative ion (anion) is called non-metallic character or electronegativity. The elements having high electro-negativity have a higher tendency to gain electrons and form anion. Down the group, electronegativity decreases due to increase in atomic size and across the period, from left to right electronegativity increases due to decrease in atomic size Which of the following correctly represents the decreasing order of metallic character of Alkali metals plotted in the graph?

The alkaline earth metals have less electropositive or metallic character as compared to those of alkali metals and their electropositive or metallic character increases down the group. Explain with reasons.