Name :
(a) three elements that have a single electron in their outermost shells.
(b) two elements that have two electrons in their outermost shells.
(c) three elements with filled outermost shells.
(a) The three elements that have a single electron in their outermost shells are-
Lithium : Atomic number – 3(2, 1);
Sodium : Atomic number – 11(2, 8, 1);
Potassium : Atomic number – 19(2, 8, 8, 1).
(b) The two elements that have two electrons in their outermost shells are
Beryllium : Atomic number – 4(2, 2);
Calcium : Atomic number – 20(2, 8, 8, 2)
(c) Three elements with filled outermost shells are-
Helium : Atomic number – 2(2);
Neon : Atomic number – 10(2, 8);
Argon : Atomic number – 18(2, 8, 8).
Related Articles
- (a) Name three elements that have a single electron in their outermost shells.(b) Name two elements that have two electrons in their outermost shells. (c) Name three elements with completely filled outermost shells.
- Three elements A, B and C have 3, 4 and 2 electrons respectively in their outermost shell. Give the group number to which they belong in the Modern Periodic Table. Also, give their valencies.
- 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 its first shell?
- The electrons in the atoms of four elements A, B, C and D are distributed in three shells having 1, 3, 5 and 7, electrons respectively in their outermost shells. Write the group numbers in which these elements are placed in the Modem Periodic Table. Write the electronic configuration of the atoms of B and D, and the molecular formula of the compound formed when B and D combine.
- Covalent bonds are formed by the __________ of electrons between two atoms so that both can achieve a completely filled outermost shell.
- The electrons present in the outermost shell are called(a) valency electrons (b) octate electrons(c) duplet electrons (d) valence electron.
- Draw a sketch of Bohr’s model of an atom with three shells.
- Summarise the rules for the writing of the distribution of electrons in various shells for the first eighteen elements.
- Atoms of eight elements A, B, C, D, E, F, G, and H have the same number of electron shells but different number of electrons in their outermost shells. It was found that elements A and G combine to form an ionic compound. This ionic compound is added in a small amount to almost all vegetables and dishes during cooking. Oxides of elements A and B are basic in nature while those of elements E and F are acidic. The oxide of element D is, however, almost neutral. Based on the above information, answer the following questions:(a) To which group or period of the periodic table do these elements belong?(b) What would be the nature of compound formed by a combination of elements B and F?(c) Which two of these elements could definitely be metals?(d) Which one of the eight elements is most likely to be found in gaseous state at room temperature?(e) If the number of electrons in the outermost shell of elements C and G be 3 and 7 respectively, write the formula of the compound formed by the combination of C and G.
- Atoms of different elements with the same number of occupied shells are placed in the same _________________________.
- Na+ has completely filled K and L shells. Explain.
- Find all elements in array which have at-least two greater elements in C++
- State the number of electrons present in the outermost shell of the atoms of the following elements :(i) Neon (ii) Chlorine
- Given below are some elements of the modern periodic table: 4Be, 9Fe, 14Si, 19K, 20Cai. Select the element that has one electron in the outermost shell and write its electronic configuration.ii. Select two elements that belong to the same group. Give reasons for your answer.iii. Select two elements that belong to the same period. Which one of the two has bigger atomic size?
- 8 Types of Linux Shells
Kickstart Your Career
Get certified by completing the course
Get Started