Periodic classification of elements class 10 Important MCQ

Periodic classification of elements class 10 Important MCQ

Question:1 At present, ———elements are known to us,

1. 94
2. 104
3. 114
4. None of these

Question:2 Around the year 1800, only ——-elements were known

1. 10
2. 20
3. 30
4. None the these

Question:3 The earliest attempt to classify the element resulted in grouping the then known elements as Metals and Non-Metals

1. true
2. false

Question:4 who tried to arrange the elements with similar properties into groups and also identified some groups having three elements each called these groups triads,

1. Mosley
2. Mendleev
3. Dobreiner

Question:5 identify the incorrect one

1. Triad were written in the order of increasing atomic numbers
2. The atomic mass of the middle element was roughly the average of the atomic masses of the other two elements
3. Triads consisting of lithium (Li) , sodium (Na) and potassium (k) with the respective atomic masses 6.9,2.0 and 39.0

Question:6 identify the incorrect statement

1. John Newlands, an English scientist arranged the then known elements in the order of increasing atomic masses
2. he started with the elements having the lowest atomic mass (hydrogen ) and ended at thorium which was the 56th elements
3. he found that every seventh element had properties similar to that of the first he compared this of the octaves found in music therefore he called it the law of octaves ,

Question:7 identify the incorrect statement about Newlands law of octaves,

1. The properties of lithium and sodium were found to be the same
2. sodium is the eighth element after lithium
3. similarly beryllium and magnesium resemble each other
4. his periodic table was based on atomic number

Question:8 it was found that the law of octaves was applicable only upto—-as after that element every eighth element did not possess properties similar to that of the first

1. Magnesium
2. Iodine
3. calcium
4. None of these

Question:9 identify the incorrect statement about newlands law of octaves,

1. It was assumed by newlands that only 56 elements existed in nature and no more elements would be discovered in the future,
2. But later on several new elements were discovered who properties did not fit into the law of octaves
3. In order to fit elements into his table newlands adjusted two elements in the same slot, but also put some unlike elements under the same note,
4. thus newlands law of Octaves worked well with heavier elements only

Question:10 The main credit for classifying elements goes to ——— a Russian chemist

1. Mendleev
2. newland
3. mosley
4. None of these

Question:11 In Mendleev periodic table elemets were arranged on the basis their fundamental property, the atomic mass and also on the similarity of chemical properties,

1. true
2. false

Question:12 identify the incorrect statement about mendleev’s

1. when Mendleev started his work 63 elements were known
2. he examined the relationship between the atomic masses of the elements and their physical and chemical properties
3. Among chemical properties, Mendeleev concentrated on the compounds formed by elements with nitrogen properties
4. he selected hydrogen and oxygen as they are very reactive and formed compounds with most elements

Question :13 Mendeleev formulated a periodic law which states that the properties of elements are the periodic function of their ————

1. Atomic number
2. Number of neutrons
3. Atomic mass
4. None of these

Question:14 identify the correct statement,

1. Mendeleeev’s periodic table contains vertical columns called groups and Horizontal rows called , rows called periods
2. In the formula fox Oxides and hydrides at the top of the columns the letter R, is used to represent any of the elements in the group
3. there were a few instances where Mendeleev had to place an element with a slightly greater atomic mass before an element with a slightly lower atomic mass
4. the sequence was inverted so that elements with similar properties could be grouped together, for example, cobalt (atomic mass 58.9) appeared before nickle

Question:15 which group was added in Mendeleev’s periodic table?

1. I group
2. VIII group
3. Zero group
4. V group

Question:16 name the most electronegative element of periodic table?

1. Chlorine
2. Bromine
3. Fluorine
4. Iodine

Question:17 Out of F, and CI which has higher electron affinity ?

1. CI
2. F
3. both have same
4. None

Question:18 what type of oxide would eka-Aluminium form ?

1. EO₃
2. E₃O₂
3. E₂O₃
4. EO

Question:19 The element with atomic number 9 resembles the element with atomic number

1. 35
2. 27
3. 17
4. 8

Question20 why N is more electronegative than phosphorous?

1. because it has less mass than phosphorous
2. because it has half filled valence shell
3. because it forms so many compounds
4. because it has small size than phosphorous

Answers

Q,No	Answer	Q,No	Answer
1	C	11	A
2	C	12	C
3	A	13	C
4	C	14	A
5	A	15	C
6	C	16	C
7	D	17	A
8	C	18	C
9	D	19	C
10	C	20	D