MCQ Questions for Class 10 Science Periodic Classification of Elements with Answers
Q1. Which of the following statements/statements is/are correct regarding elements?
(1) 118 elements are known to us.
(2) out of 118 elements, only 94 elements are found naturally.
(a) (1) statement is correct
(b) (2) statement is correct
(c) (1) and (2) Both statements are correct
(d) None of these statements are correct
Ans. (1) and (2) Both statements are correct
Q2. Which of the following classifications are correct given by Döbereiner.
1. Every eighth element showed properties similar to that of the first.
2. Arranged in increasing order of their masses.
3. Mass of the middle element was equal to the average mass of the other two elements.
(a) (1) and (2) classifications are correct
(b) (2) and (3) classifications are correct
(c) (1) and (3) classifications are correct
(d) All the above classifications are correct
Ans. (2) and (3) classifications are correct
Q3. Which of the following is the drawback of Döbereiner
(a) Isotopes were not given any position in this Döbereiner Triads.
(b) Döbereiner assumed that only 56 elements existed in nature and no new element would be discovered.
(c) At that time only (54) elements were known, and the grouping was not done for all the elements so, it was not accepted.
(d) Hydrogen is not correctly placed in Döbereiner Triads.
Ans. At that time only (54) elements were known, and the grouping was not done for all the elements so it was not accepted.
Q4. In which year, John Newlands, an English scientist, arranged the then-known elements in the order of increasing atomic masses.
(a) In 1817
(b) In 1866
(c) In 1834
(d) none of the above
Ans. In 1866
Q5. What is John Newland’s Law of Octaves?
(a) Mass of the middle element was equal to the average mass of the other two elements.
(b) Every eighth element showed properties similar to that of the first.
(c) Both are the Newland’s Law of Octaves
(d) None of these is the Newland’s Law of Octaves
Ans. Every eighth element showed properties similar to that of the first.
Q6. Which of the following is/are incorrect “Drawbacks of Newland’s Octaves”?
1. He could group the elements only till calcium, after Ca the remaining elements did not follow the law of Octaves.
2. Newland assumed that only 56 elements existed in nature and no new element would be discovered.
3. He tried to jumble a few elements to make it possible that the Law of Octaves is followed.
4. He adjusted two elements, cobalt and nickel by placing them in the same group of fluorine, chlorine and bromine.
(a) (1) is incorrect “Drawbacks of Newland’s Octaves”
(b) (2) is incorrect “Drawbacks of Newland’s Octaves”
(c) (3) and (4) are incorrect “Drawbacks of Newland’s Octaves”
(d) none of the above is incorrect.
Ans. None of the above is incorrect.
Q7. When Mendeleev come how many elements were known at the time
(a) 54 elements were known at that time.
(b) 56 elements were known at that time.
(c) 63 elements were known at that time.
(d) 118 elements were known at that time.
Ans. 63 elements were known at that time.
Q8. Which of the following is the achievement of mendeleev?
(a) Noble gases were not discovered then. After discovery, they got a separate group without disturbing the elements in the table.
(b) He left 3 gaps and he predicted 3 elements as Eka boron, Eka aluminium and Eka silicon. discovered later they were Scandium, Gallium and Germanium.
(c) Both are the achievements of Mendelee.
(d) None of these is the achievement of Mendelee.
Ans. Both are the achievements of Mendelee.
Q9. Which of the following is the drawback of Mendeleev?
(a) Mass of the middle element was equal to the average mass of the other two elements.
(b) He adjusted two elements, cobalt and nickel by placing them in the same group of fluorine, chlorine and bromine.
(c) At that time only a few elements (54) were known, the grouping was not done for all the elements so, it was not accepted.
(d) Isotopes were not given any position in this table
Ans. Isotopes were not given any position in this table
Q10. When does atomic size increase in the modern periodic table?
(a) moving from left to right
(b) moving from right to left
(c) moving from top to bottom
(d) both (b) and (c)
Ans. both (b) and (c)
Q11. When does metallic character decrease in the modern periodic table?
(a) moving from left to right
(b) moving from right to left
(c) moving from bottom to top
(d) both (a) and (c)
Ans. both (a) and (c)
Q12. On moving from left to right in the period, the number of valence electrons?
(a) increases from 1 to 8.
(b) decrease from 1 to 8.
(c) first, increase 1 to 4 then decrease
(d) none of these
Ans. increases from 1 to 8.
Q13. Did Döbereiner’s triads also exist in the columns of Newland’s Octaves?
(a) Yes, it exists in Newland’s octave. It is Li, Na and K.
(b) Yes, it exists in Newland’s octave. It is Ca, Sr and Ba.
(c) Yes, it exists in Newland’s octave. It is Cl, Br and I.
(d) Yes, it exists in Newland’s octave. It is Li, Ca and Cl.
Ans. Yes, it exists in Newland’s octave. It is Li, Na and K.
Q14. What were the criteria used by Mendeleev in creating his Periodic Table?
(a) Increasing order of the atomic mass of the elements.
(b) All elements in a group with similar properties.
(c) The formula of oxides and hydrides formed by an element.
(d) All the above criteria were used by Mendeleev.
Ans. All the above criteria were used by Mendeleev.
Q15. In the Modern Periodic Table, which are the metals among the first ten elements.
(a) Lithium and boron are metals.
(b) beryllium and nitrogen are metals.
(c) Lithium and beryllium are metals.
(d) Fluorine and neon are metals.
Ans. Lithium and beryllium are metals.
Q16. Which is not true about noble gases?
(a) They are non-metallic in nature
(b) They exist in atomic form
(c) They are radioactive in nature
(d) Xenon is the most reactive among these
Ans. They are radioactive in nature
Q17. Name three elements discovered later, which filled gaps left by Mendeleev for them.
(a) eka-boron, eka-aluminium and eka-silicon.
(b) Scandium, gallium and germanium.
(c) boron, aluminium and silicon
(d) None of the above
Ans. Scandium, gallium and germanium.
Q18. What are isotopes?
(a) the atoms of the same element having the same atomic number but a different mass number.
(b) the atoms of the same element have the same atomic mass but different atomic numbers.
(c) the atoms of different elements have the same atomic number but different mass numbers.
(d) the atoms of the same element having the same atomic number and mass number also.
Ans. the atoms of the same element have the same atomic number but different mass numbers.
Q19. Which of the following is the Modern Periodic Law.
(a) Properties of elements are a periodic function of their mass number.
(b) Properties of elements are a periodic function of their atomic number.
(c) Properties of elements are periodic by protons and electrons in the elements
(d) None of the above
Ans. Properties of elements are periodic functions of their atomic number.
Q20. An element (A) belongs to the 3rd period and group one of the periodic table. find the name of the matter and the name of its family?
(a) Lithium and its family is alkali.
(b) Sodium and its family is alkali.
(c) potassium and its family alkali.
(d) none of these
Ans. Sodium and its family is alkali.
Q21. A metal ‘X’ is in the first group of the Periodic Table. What will be the formula of its oxide?
(a) XO
(b) X2O
(C) X2O3
(d) XO2
Ans. X2O
Q22. Which of the following are the correct characteristics of groups?
(a) All elements in a group show the same number of valence electrons in their outermost shell, hence showing similar properties.
(b) As we move top to bottom in a group the atomic radius goes on increasing and there is a slight gradation in properties.
(c) On moving down the group, the metallic character goes on
increasing
(d) All the above characteristics are correct.
Ans. All the above characteristics are correct.
Q23. Which of the following are incorrect characteristics of Period?
(a) The atomic size decreases from left to right in a period.
(b) The number of Valence Electrons increases from 1 to 8 along the period.
(c) Valency also increases from 1 to 8 during the period.
(d) Size of the atom goes on decreasing in the period.
Ans. Valency also increases from 1 to 8 during the period.
Q24. The electronic configuration of an atom is 2, 8, and 7. Given its nature of oxide.
(a) Acidic oxide
(b) Basic oxide
(c) neutral oxide
(d) none of these
Ans. Acidic oxide
Q25. What are metalloids?
(a) The elements which show properties of metals are called semi-metals or metalloids.
(b) The elements which show properties non-metal are called semi-metals or metalloids.
(c) The elements which show some properties of metal and some properties of nonmetal are called semi-metals or metalloids.
(d) none of the above
Ans. The elements which show some properties of metal and some properties of nonmetal are called semi-metals or metalloids.