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Question
Fill in the blank and rewrite the completed statement:
________ group in the periodic table contains elements that are all gases at room temperature.
Solution
The 18th group in the periodic table contains elements that are all gases at room temperature.
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RELATED QUESTIONS
How many groups and periods are there in the modern periodic table?
Na, Mg and Al are the elements of the same period of Modern Periodic Table having, one, two and three valence electrons respectively. Which of these elements (i) has the largest atomic radius, (ii) is least reactive? Justify your answer stating reason for each case.
Write the number of horizontal rows in the modern periodic table. What are these rows called?
Which element has a total of three shells, with four electrons in its valence shell?
Which element has a total of two shells, with three electrons in its valence shell?
Classify the following elements into metals, non-metals and metalliods
As, C, Hg, Mg, S, Si
The following table shows the electronic configuration of the elements W, X, Y, Z:
| Element | w | x | y | z |
| Electronic configurations |
2, 8, 1 | 2, 8, 7 | 2, 5 | 1 |
Answer the following questions based on the table above:
1) What type of Bond is formed between :
a) W and X
b) Y and Z
2) What is the formula of the compound formed between :
a) X and Z
b) W and X
In the following set of element, one element does not belong to the set. Select this element and state why it does not belong:
Calcium, Magnesium, Sodium, Beryllium
Name the element which is in first group and third period.
Why does the size of the atoms progressively become smaller when we move from sodium (Na) to chlorine (Cl) in the third period of the periodic table?
In terms of electronic configurations, explain the variation in the size of the atoms of the elements belonging to the same period and same group ?
Five elements A, B, C, D and E have atomic numbers of 2, 3, 7, 10 and 18 respectively. The elements which belong to the same period of the periodic table are:
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(b) B, C, D
(c) A, D, E
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The correct increasing order of the atomic radii of the elements oxygen, fluorine and nitrogen is:
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(d) F, O, N
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Elements in the same periods have equal valency.
Why are noble gases placed in a separate group?
State the valency of the elements of periods 3 and write the formula of their oxides.
An element X belong to 4th period and 17th group, state.
Write the formula of the compound formed when it reacts with `(27)/(13) y `
Name the element which has the electronic configuration 2, 8, 3?
Chorine in the periodic table is surrounded by the elements with atomic number 9, 16, 18 and 35.
Which of these have physical and chemical properties resembling chlorine.
On the basis of electronic configuration, how will you identify the first and the last element of a period?
Taking into consideration the period of the elements given below, answer the following questions:
| Elements | Atomic Radius (pm) |
| O | 66 |
| B | 88 |
| C | 77 |
| N | 74 |
| Be | 111 |
| Li | 152 |
- Arrange the above elements in decreasing order of their atomic radii.
- State the period to which the above elements belong.
- Why this arrangement of elements is similar to the above period of modern periodic table?
- Which of the above elements have the biggest and the smallest atom?
- What is the periodic trend observed in the variation of atomic radius while going from left to right within a period?
Fill in the blank
Oxidising property ________from fluroine to iodine because the power to accpet electron decreases.
State whether the following statement is true or false
On moving horizontally across a period, number of valence electrons increases from one to eight.
Explain
Size of atom changes when it loses or gain electron
Select the correct answer
Most reactive character among the elements given below is found in
The following table represents the first period of the modern periodic table. Study the table and answer the questions that follow:
(i) Write the formula of the sulphate of the element with atomic number 13.
(ii) What type of bonding will be present in the oxide of the element with atomic number 1?
(iii) Which feature of the atomic structure accounts for the similarities in the chemical properties of the elements in group VIIA of the periodic table?
(iv) Name the element which has the highest ionization potential.
(v) How many electrons are present in the valence shell of the element with atomic number 18?
(vi) What is the name given to the energy released, when an atom in its isolated gaseous state accepts an electron to form an anion?
(vii) What is the electronic configuration of the element in the third period which gains one electron to become an anion?
(viii) Fill in the blanks:
The atomic size ______ as we move from left to right across the period, because the ______ increases, but the ______ remains the same.
The following questions refer to the Periodic Table.
What is the common feature of the electronic configurations of the elements in group 7?
Give the number of the group and the period of elements having three shells with three electrons in valence shell.
Choose the most appropriate answer from the following list of oxides which fit the description.
An amphoteric oxide.
Arrange the following as per instruction given in the bracket.
K, Pb, Ca, Zn (increasing reactivity)
Arrange the following as per instruction given in the bracket.
Li, K, Na, H ( decreasing order of their potential ionisation )
With reference to the variation of properties in the Periodic table, which of the following is generally true?
Write the electronic configuration of element 17T35.
- What is the group number of T?
- What is the period number of T?
- How many valence electrons are there in an atom of T?
- What is the valency of T?
- Is it a metal or non-metal?
- State number of protons and neutrons in T.
Name and state the following with reference to the elements of the first three periods of the periodic table.
Metalloid in Period 3.
Supply the missing word from those in bracket:
If an element has one electron in its outermost energy level [shell] then it is likely to be _______.
What is meant by a Group in the Periodic Table?
State the property trends in general of elements on moving down in a group of the periodic table.
Name or state following with reference to the element of the first three periods of the periodic table.
A non-metal in period 2 which is tetravalent.
Which of the following would weigh the least?
(Atomic masses C = 12, 0 = 16, Na = 23)
