In the Modern Periodic Table, the electronic configuration of an element determines the number of valence electrons whereas the position of the atom is determined by the valence electrons.
Nitrogen (atomic number 7) and phosphorus (atomic number 15) belong to group 15 of the Periodic Table. Write the electronic configuration of these two elements. Which of these will be more electronegative? Why?
Nitrogen: Atomic number - 7 Electronic configuration - 1s2 2s2 2p3 Nitrogen: Atomic number - 15 Electronic configuration - 1s2 2s2 2p6 3s2 3p3 The number of shell increases in the periodic table...
The position of three elements A, B and C in the Periodic Table are shown below–
Group 16 Group 17 - - - A - - B C (a) State whether A is a metal or non-metal. (b) State whether C is more reactive or less reactive than A. (c) Will C be larger or smaller in size than B?...
An atom has electronic configuration 2, 8, 7. (a) What is the atomic number of this element? (b) To which of the following elements would it be chemically similar? (Atomic numbers are given in parentheses.) N(7), F(9), P(15), Ar(18)
(a)The element is Chlorine (Cl) and the atomic number of chlorine is 17. (b) The atom with the electronic configuration of 2, 8, 7 which is the chlorine is chemically identical to Fluorine (F) which...
(a) What property do all elements in the same column of the Periodic Table as boron have in common? (b) What property do all elements in the same column of the Periodic Table as fluorine have in common?
(a) All the elements are in the same boron column (group 13). Thus, they have three electrons in their valence shells. Besides, non-metallic boron, all other elements (i.e., aluminum, gallium,...
Which element has? (a) Two shells, both of which are completely filled with electrons? (b) The electronic configuration 2, 8, 2? (c) A total of three shells, with four electrons in its valence shell? (d) A total of two shells, with three electrons in its valence shell?(e) twice as many electrons in its second shell as in its first shell?
(a) Neon (Ne) has two shells in which both are completely filled with electrons. (b) Magnesium (Mg) has the electronic configuration 2, 8, 2. (c) Silicon (Si) has a total of three shells, with four...
Element X forms a chloride with the formula XCl2, which is a solid with a high melting point. X would most likely be in the same group of the Periodic Table as (a) Na (b) Mg (c) AI (d) Si
Identification: Element X - Magnesium (Mg) containing valency of 2. Explanation: When Mg is combined with chloride (Cl), it forms Magnesium Chloride (MgCl2).
Which of the following statements is not a correct statement about the trends when going from left to right across the periods of Periodic Table. (a) The elements become less metallic in nature. (b) The number of valence electrons increases. (c) The atoms lose their electrons more easily. (d) The oxides become more acidic
Correct Answer: (c) The atoms lose their electrons more easily Explanation: Atoms do not lose their electrons easily because as we move from left to right across the periodic table, the non-metallic...
By considering their position in the Periodic Table, which one of the following elements would you expect to have maximum metallic characteristic? Ga/Ge/As/Se/Be
The elements that are expected to have the most metallic character are Be and Ga. The tendency to lose electrons is greater in Ga than the Be as the size of Ga is bigger. Thus, the element Ga have...
In the Modern Periodic Table, which are the metals among the first ten elements?
The metals among the first ten elements in the modern periodic table are, Lithium Beryllium
(a) Lithium, sodium, potassium are all metals that react with water to liberate hydrogen gas. Is there any similarity in the atoms of these elements? (b) Helium is an unreactive gas and neon is a gas of extremely low reactivity. What, if anything, do their atoms have in common?
(a) Lithium, sodium, potassium are the metals that are unstable because of the unfilled outermost shells. This is the reason that they react with water in order to release hydrogen and these metals...
Name 1. Three elements that have a single electron in their outermost shells. 2. Two elements that have two electrons in their outermost shells. 3. Three elements with filled outermost shells
Lithium (Li), Sodium (Na) and potassium (k) are the three elements that have only one electron in their outermost shells. Magnesium (Mg) and Calcium (Ca) are the two elements that contains...
Name two elements you would expect to show chemical reactions similar to magnesium. What is the basis for your choice?
I think that the elements Calcium and Beryllium are expected to show chemical reactions that are similar to the element magnesium as these elements belong to the same group having 2 valence...
How could the Modern Periodic Table remove various anomalies of Mendeleev’s Periodic Table?
The Modern periodic table is arranged in order of their atomic number. This removes inconsistencies in relation to certain pairs of the elements present in the Mendeleev’s periodic table. The atomic...
Why do you think the noble gases are placed in a separate group?
The noble gases have been classified as separate group because of their inert nature as they are also called as inert gases. Noble gases are present in low concentration in our atmosphere. They are...
What were the criteria used by Mendeleev in creating his Periodic Table?
Mendeleev focused on a variety of chemicals made up of elements containing Hydrogen and Oxygen. Among the material, he saw the interrelationships between the mass of many atoms of various elements...
Besides gallium, which other elements have since been discovered that were left by Mendeleev in his Periodic Table? (Any two)
The elements that are left by the Mendeleev’s Periodic Table besides gallium are, Germanium Scandium
Use Mendeleev’s Periodic Table to predict the formulae for the oxides of the following elements: K, C, AI, Si, Ba.
According to the Mendeleev’s Periodic Table, Potassium (K) belongs to group IA with a valency of 1. Formula - K2O Carbon (C) belongs to group IV A with a valency of 4. Formula - C2O4 or CO2 Aluminum...
What were the limitations of Newlands’ Law of Octaves?
Limitations of Newlands’ Law of Octaves: Newlands Octave law applies only to the elements till Calcium. Newland estimates that there are a total of 56 elements in nature and that there are no more...
Compare and contrast the arrangement of elements in Mendeleev’s Periodic Table and the Modern Periodic Table.
Mendeleev’s Periodic Table Modern Periodic Table In the Mendeleev’s Periodic Table, the arrangement of the elements are according to the increasing order of the element’s atomic mass. In the Modern...
What were the limitations of Döbereiner’s classification?
Limitations of Döbereiner’s classification: They do not work at elements which have very low or high mass. All elements could not fit into Dobereiner's traids. As the methods of calculating the...