![]() ![]() ![]() Which of the following is the correct representation of the element?31X1531X1616X1515X16 The number of electrons in an element X is 15 and the number of neutrons is 16.(a) What is meant by (i) atomic number, and (ii) mass number, of an element? Explain with the help of an example.(b) What is the relation between the atomic number and mass number of an element?(c) If an element M has mass number 24 and atomic number 12, how many neutrons does its atom contain?.Why?(e) What type of ion, cation or anion, will be formed by an atom of element E? Why?(f) Write the symbol of the ion formed by an atom of element E.(g) What could element X be? An atom of element E contains 3 protons, 3 electrons and 4 neutrons :(a) What is its atomic number?(b) What is its mass number?(c) Write the electronic configuration of the element E.(d) State whether element E is a metal or non-metal.An atom of an element X may be written as 94X.(a) What does the figure 9 indicate?(b) What does the figure 4 indicate?(c) What is the number of protons in atom X?(d) What is the number of neutrons in atom X?(e) What is the number of electrons in atom X?(f) How many electrons are there in the outermost shell of an atom of element X?(g) Write the symbol of ion formed by an atom of element X.(Hint: The mass of an ion is the same as that of an atom of the same element. Calculate the number of aluminium ions present in 0.051 g of aluminium oxide. ![]() (k) The subatomic particle not present in a hydrogen atom is. (j) The maximum number of electrons that can go into the M shell is. (i) The maximum number of electrons that can be accommodated in L shell are. (h) The anode rays obtained from hydrogen gas consist of particles called. (g) Cathode rays are a beam of fast-moving. (f) Almost all the mass of an atom is concentrated in a small region of space called the. (e) If the nucleus of an atom has atomic number 17, mass number 37 and there are 17 electrons outside the nucleus, the number of neutrons in it is. electrons.(d) An atom of an element has 11 protons, 11 electrons and 12 neutrons. (c) An atom has atomic mass number 23 and atomic number 11. (b) The total number of protons and neutrons in the nucleus of an atom is called its. Fill in the blanks in the following statements :(a) The number of protons in the nucleus of an atom is called its.What is the number of protons and neutrons in it? What is the atomic number of the element? State one drawback of Rutherford's model of the atom.(b) The mass number of an element is 23 and it contains 11 electrons. (a) Describe the Rutherford's model of an atom.The atomic number of element Y is most likely to be :(a) 8 (b) 12 (c) 10 (d) 14 The number of electrons in an ion Y2+ is 10.The number of electrons in its ion E2– will be :(a) 16 (b) 18(c) 15 (d) 14 The atomic number of an element E is 16.What is the number of valence electrons in :(a) sodium ion, Na+(b) oxide ion, O2–.What would be the (a) atomic number, (b) mass number, (c) the number of electrons, and (d) the number of valence electrons, per atom of this element? The nucleus of an atom has 5 protons and 6 neutrons.The atom of an element X contains 17 protons, 17 electrons, and 18 neutrons whereas the atom of an element Y contains 11 protons, 11 electrons, and 12 neutrons.(a) What type of ion will be formed by an atom of element X ? Write the symbol of the ion formed.(b) What will be the number of (i) protons (ii) electrons, and (iii) neutrons, in the ion formed from X?(c) What type of ion will be formed by an atom of element Y ? Write the symbol of the ion formed.(d) What will be the number of (i) protons (ii) electrons, and (iii) neutrons, in the ion formed from Y?(e) What is the atomic mass of (i) X, and (ii) Y?(f) What could the elements X and Y be?.Which of the following statement is always correct?(a) an atom has equal number of electrons and protons (b) an atom has equal number of electrons and neutrons (c) an atom has equal number of protons and neutrons (d) an atom has equal number of electrons, protons and neutrons.What is the number of electrons in the ion?(a) 13 (b) 10 (c) 14 (d) 16 The mass number of atom of this element is 27 and the number of neutrons is 14. The ion of an element has 3 positive charges.
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