According to IUPAC recommendations, the number of groups in the long form of the periodic table is :-
In chemistry, a group (also known as a family) is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table.
Modern periodic law was proposed by:
Modern periodic law was proposed by Henry Moseley in 1913. According to the modern periodic law, the properties of the elements and their compounds are a periodic function of their atomic numbers..
The least metallic element of group 1 is :-
The group 1 elements in the periodic table are known as the alkali metals. They include lithium, sodium and potassium, which all react vigorously with air and water.
In the third period of the periodic table the element having smallest size is
As we move along a period, size decreases so, Cl have lowest size among all.
Which of the following statement is not correct about the trends when going from left to right across the periodic table?
The correct option is C.
The characteristic chemical property of a metal atom is to lose one or more of its electrons to form a positive ion. However, certain metals lose electrons much more readily than others. In particular, cesium (Cs) can give up its valence electron more easily than can lithium (Li).
The law of octaves was proposed by :-
An English scientist called John Newlands put forward his law of octaves in 1864. He arranged all the elements known at the time into a table in order of relative atomic mass. When he did this, he found that each element was similar to the element eight places further on.
The number of periods in the long form of the periodic table is :-
A period is a horizontal row of the periodic table. There are seven periods in the periodic table, with each one begining at the far left.
Which of the following has the maximum non-metallic character ?
Non metallic character decreases as we move down the group. In a group, the size of an element increases because there is an addition of new shell and electron is added in that shell. Hence, fluorine has the most non metallic character.
Which of the following sets of elements do not belong to the same group ?
We know, Phosphorus ( P) belongs to group 15 , Sulphur (S) belongs to group 16 and chlorine belongs to group ( 17) . So, option ( c) is the correct one.
Which of the following has lowest number of electrons in the valence shell ?
As we can see, the no. of electrons in the valence shell of oxygen (8) is => 6
In valence shell of carbon (6) => 4
In valence shell of Nitrogen (7) => 5
In valence shell of boron (5) => 3
Therefore, boron has the lowest electron in the valence shell.
An element has an atomic number of 15 with which of the following elements will it show similar chemical properties.
The valence electrons of the atomic number 15 has 5 electrons in its outermost shell . Nitrogen also has 5 electrons in it's outer shell. It also belongs to 15 th group and has same chemical properties, others have 2,8 and 6 in their outermost shell.
Which of the following has largest atomic size ?
The atomic size of Be is 112 pm, the atomic size of C is 70 pm, the atomic size of oxygen is 60 pm and the atomic size of fluorine is 71 pm. So, the atomic size of Be is largest here.
Which of the following belongs to group 18 ?
What is the basis of long form of the periodic table ?
Which one is more metallic element ?
Element X forms a chloride with the formula XCl2, Which is a solid with a high metingpoint, X would most likely be in the same group of the periodic table as :-
The correct answer is B as elements of group Na form XCl halide.
Elements of group Mg form XCl2 halide.
Elements of group Al form XCl3 halide.
Elements of group Si form XCl4 halide.
As an element, X forms a chloride with the formula XCl2 which is solid with a high melting point. X would most likely be in the same group of Mg.
How many groups and periods are present in the modern periodic table?
Electropositive character of elements in a period ___________ from left to right
Metallic character decreases across a period from left to right. On the other hand non-metallic character increases with increase in atomic number across a period.
How does the valency vary in going down a group?
What is the nature of an element having atomic number 20?
The element with atomic number 20 is Calcium (Ca) and it has metallic character as it loses two valence electrons easily to complete it's octet.
Which group elements are called transition metals?
Many scientists describe a "transition metal" as any element in the d-block of the periodic table, which includes groups 3 to 12 on the periodic table. In actual practice, the f-block lanthanide and actinide series are also considered transition metals and are called "inner transition metals".
There are a number of properties shared by the transition elements that are not found in other elements, which results from the partially filled d shell. These include
1. the formation of compounds whose color is due to d–d electronic transitions
2. the formation of compounds in many oxidation states, due to the relatively low energy gap between different possible oxidation states[
3. the formation of many paramagnetic compounds due to the presence of unpaired d electrons. A few compounds of main group elements are also paramagnetic (e.g. nitric oxide, oxygen)
What property of all elements in the column of the periodic table as fluorine have in common?
The correct answer is D as All of them have valence electrons equal to seven and this can accept one electron to complete their octet
Which group of periodic table does Ge belongs to?
The carbon group is a periodic table group consisting of carbon (C), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), and flerovium (Fl). It lies within the p-block. In modern IUPAC notation, it is called Group 14.
An element belongs to period 2 and group 2 th number of valence electrons in the atoms of this element is.
In Newlands law of octaves elements are arranged in order of
In 1864, Newlands arranged the known 56 elements in the order of increasing atomic masses. He observed that the properties of every eighth element are similar to the properties of the first element. Based on this observation, he proposed the Law of Octaves for the classification of elements. Law of Octaves: When the elements are arranged in the increasing order of their atomic masses, the properties of every eighth element are similar to the first.