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what is diagonal relationship?explain its causes.
pls.explain why fluorine has less negative electron gain enthalpy than chlorine.
what is penultimate shell
Why do we need to classify elements?
What is meant by predominantly ionic?
HOW WOULD YOU JUSTIFY THE PRESENCE OF 18 ELEMENTS IN THE FIFTH PERIOD OF THE PERIODIC TABLE?
A+2is isoelectronic with 'CO2' & has ( z+2 ) neutrons.
(A) Mass no. of A+2is 50
(B) Last electron enters in 's' orbital in element A
(C) No. of Unpaired electron in A is 4
(D) During formation of A+2, electrons are removed from both s & d subshell.
explain the electron gain enthalpy?
oxidation state and covalency of aluminium in (AlCl(H2O)5)+2 are same or differrent? justify
what is ionization enthalpy
which of the following represents most electropositive element
a- [He]2s1
b-[He]2s2
c-[Xe]6s1
d- [Xe]6s2
what is the difference between valency and covalency.
Difference between Electronegativity and Electron Gain Enthalpy..??
the value of IP1, IP2 , IP3 and IP4 of an atom are respectively 7.5 eV, 25.6 eV , 48.6 eV, 170.6 eV. the electronic configuration of the atom will be--
A) 1s2,2s2,2p6,3s1
B)1s2,2s2,2p6,3s2,3p1
C)1s2,2s2,2p6,3s2,3p3
D)1s2,2s2,2p6,3s2
Pls. ans.
Explain the diagonal relation ship between Li and Mg
effective nuclear charge in case of an ion is equal to
a- its actual nuclear charge
b- nuclear charge+ charge on the ion
c- nuclear charge+ screening constant
d- nuclear charge - screening constant
Is there any trick 2 learn periodic table?
Ca2+ is isoelectronic with
a- Mg2-
b-Kr-
c-Ar
d-Na+
please explain why chlorine is more electonegative than flourine however in p-block metallic character increses? please don't repeat the same answer.
the outer most electronic configuration of the most electronegative element is
a- ns2np3
b- ns2np4
c- ns2np5
d- ns2np6
What is electron gain enthalpy?How does it vary in group and period?explain.
In which of the following sets elements have nearly same atomic radii and why??
a)Fe,Co,Ni,Cu
b)O,S,Se,Te
c)Mg,Ca,Cr,Ba
d)Li,Be,B,C
Consider the following species :
N3-, O2-, F-, Na+, Mg2+ and Al3+
(a) What is common in them?
(b) arrange them in the increasing ionic radii?
True / False :
(A) No. of electrons having l = 0 in Pd is 10.
(B)The value of Zeff. for 3rd electron of Cr & Mn is same as no. of electron in 'd' subshell are same.
(C) Multiplicity of Fe is equal to Ni2+
what is differentiating electron
WHICH HAS HIGHER LATTICE ENTHALPY AND WHY?
MgO AND NaCl
Mg2+ ion is smaller than O2- ion although both have same electronic configuration..why??
The electron gain enthalpy values of halogens become more negative in the order F>Cl>Br>I.
Comment on this statement
define strength of a solution?
what are the drawbacks of the long form periodic table?
Are the oxidation state and covalency of Al in [AlCl(H2O)6]2+ same??
Out of Na and Na+ which one has larger size and why?
which of the following valence electron experience maximum effective nuclear charge ?
4s1, 4p1, 3d1 , 2p3 ?? n why
Which is stable O22+ or O22-, And Why ?
What is meant by Unipositive and Dipositive ion?
Which of the following pair of elements have the same value of shielding constant for 3s electron??
a. Mn & Zn b. Fe & na c. Ar & Cl d. All of these
the 1st ionization enthalpy of calcium is greater than that of potassium because for calcium
a- the electron is removed from s-subshell
b- the effective nuclear charge is higher
c- the electron is removed from a p-subshell
d- the removal of electron does not give noble gas configuration
How to calculate screening constant for a given element ????
explain why the s-block elements are very reactive.
What is meant by penetration effect of the electrons?
what is polarising power?
why o has lower ionisation enthalpy than N and F?
Why are f-block elements called "Inner-transition elements" ?
which of the following ions does not have the configuration of argon?
a- Cl-
b- K+
c- Ca2+
D- I-
why does cl have more negative electron gain enthalpy than F ?
first ionisation energy is lowest in :
carbon, lead,silicon or tin ???
The order of first electron affinity of O , S and Se :-
(A) O>S>Se (B) S>Se>O (C) Se>O>S (D) S>O>Se
which is the largest element in the periodic table? why?
Why group 1 elements are called alkali metals?Why Group 2 elements are called alkali earth metals?
nitroge has positive electron gain enthalpy whereas oxygen has negative,however oxygen has lower ionization enthalpy than nitrogen.explain.
Arrange the following ions in the order of increasing size.
Be2+, Cl- ,S2- ,Na+, Mg2+,Br-
Also please explain why?
why is second ionization enthalpy greater than first ionization enthalpy?pls.explain
why group 17 elements called halogens...
The first member of the lanthanide series is lanthanum . True / False
Electron gain enthalpy of Oxygen and Fluorine is less negative than suceeding element S and Cl. Why?
What is Covalency?How to find the covalency of any element
neon has got more atomic radius than flourine.How?
Explain why halogens have maximum electron gain enthalpy in their respective periods.
what are typical elements and how do they differ from transision elements
what is mean by unpaired electron.........?? pls explain with examples
FULL FORM OF METAL
elements of IB and II B are called
a- normal elements
b- transition element
c- alkaline earth metals
d- alkali metals
CH4 , H2O , NH3 order of increasing bond angle around central atom
what is dsp 2 hybridization
How does atomic radius vary in a period and in a group ? How yoy explain the variation ?
increasing order of atomic radii of the elements B, Al, C, Si, is
a- si, al, c, b
b- B, C, Al,Si,
c- Al, Si, B, C
D- C, B, Si, Al
how to calculate covalency?
how we can learn periodic table fast n easily ????????plz give me ur suggstions frzzzzz
the first ionisation energy of nitrogen is greater then that of oxygen , whereas the second ionisation energy of oxygen is greater than nitrogen....WHY..??????
Alkali metals have largest atomic volume in their period--is this true?
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Syllabus
what is diagonal relationship?explain its causes.
How is it that in Schomaker and Stevenson's formula for atomic radii in case of covalent bond subtracts electonegativity (k cal/mol) from radius (angstrom) ???
pls.explain why fluorine has less negative electron gain enthalpy than chlorine.
A)Gama line in Lyman series in H--UV
B)Beta line in Balmer series in He+--UV
C)Delta line in Balmer series in H--visible
D)Delta line in Paschen series in H--infrared
Answer is all the options are correct. I have already asked this question and expert told me how to solve it but his question is new to me and I have no idea about what the wavelength must be to be in which series. So pls solve them. thanks!
what is penultimate shell
Why do we need to classify elements?
What is meant by predominantly ionic?
HOW WOULD YOU JUSTIFY THE PRESENCE OF 18 ELEMENTS IN THE FIFTH PERIOD OF THE PERIODIC TABLE?
A+2is isoelectronic with 'CO2' & has ( z+2 ) neutrons.
(A) Mass no. of A+2is 50
(B) Last electron enters in 's' orbital in element A
(C) No. of Unpaired electron in A is 4
(D) During formation of A+2, electrons are removed from both s & d subshell.
explain the electron gain enthalpy?
Q. 132. In which of the following pairs of elements the electronegativity of the first element is less than that of second element :-
(1) Zr, Hf
(2) K, Rb
(3) Cl, S
(4) None of the above
oxidation state and covalency of aluminium in (AlCl(H2O)5)+2 are same or differrent? justify
what is ionization enthalpy
which of the following represents most electropositive element
a- [He]2s1
b-[He]2s2
c-[Xe]6s1
d- [Xe]6s2
what is the difference between valency and covalency.
Difference between Electronegativity and Electron Gain Enthalpy..??
the value of IP1, IP2 , IP3 and IP4 of an atom are respectively 7.5 eV, 25.6 eV , 48.6 eV, 170.6 eV. the electronic configuration of the atom will be--
A) 1s2,2s2,2p6,3s1
B)1s2,2s2,2p6,3s2,3p1
C)1s2,2s2,2p6,3s2,3p3
D)1s2,2s2,2p6,3s2
Pls. ans.
Explain the diagonal relation ship between Li and Mg
effective nuclear charge in case of an ion is equal to
a- its actual nuclear charge
b- nuclear charge+ charge on the ion
c- nuclear charge+ screening constant
d- nuclear charge - screening constant
Is there any trick 2 learn periodic table?
Ca2+ is isoelectronic with
a- Mg2-
b-Kr-
c-Ar
d-Na+
please explain why chlorine is more electonegative than flourine however in p-block metallic character increses? please don't repeat the same answer.
the outer most electronic configuration of the most electronegative element is
a- ns2np3
b- ns2np4
c- ns2np5
d- ns2np6
What is electron gain enthalpy?How does it vary in group and period?explain.
In which of the following sets elements have nearly same atomic radii and why??
a)Fe,Co,Ni,Cu
b)O,S,Se,Te
c)Mg,Ca,Cr,Ba
d)Li,Be,B,C
Consider the following species :
N3-, O2-, F-, Na+, Mg2+ and Al3+
(a) What is common in them?
(b) arrange them in the increasing ionic radii?
True / False :
(A) No. of electrons having l = 0 in Pd is 10.
(B)The value of Zeff. for 3rd electron of Cr & Mn is same as no. of electron in 'd' subshell are same.
(C) Multiplicity of Fe is equal to Ni2+
what is differentiating electron
WHICH HAS HIGHER LATTICE ENTHALPY AND WHY?
MgO AND NaCl
Mg2+ ion is smaller than O2- ion although both have same electronic configuration..why??
The electron gain enthalpy values of halogens become more negative in the order F>Cl>Br>I.
Comment on this statement
define strength of a solution?
what are the drawbacks of the long form periodic table?
Are the oxidation state and covalency of Al in [AlCl(H2O)6]2+ same??
Out of Na and Na+ which one has larger size and why?
which of the following valence electron experience maximum effective nuclear charge ?
rn4s1, 4p1, 3d1 , 2p3 ?? n why
Which is stable O22+ or O22-, And Why ?
What is meant by Unipositive and Dipositive ion?
Which of the following pair of elements have the same value of shielding constant for 3s electron??
a. Mn & Zn b. Fe & na c. Ar & Cl d. All of these
the 1st ionization enthalpy of calcium is greater than that of potassium because for calcium
a- the electron is removed from s-subshell
b- the effective nuclear charge is higher
c- the electron is removed from a p-subshell
d- the removal of electron does not give noble gas configuration
How to calculate screening constant for a given element ????
explain why the s-block elements are very reactive.
What is meant by penetration effect of the electrons?
what is polarising power?
why o has lower ionisation enthalpy than N and F?
Why are f-block elements called "Inner-transition elements" ?
which of the following ions does not have the configuration of argon?
a- Cl-
b- K+
c- Ca2+
D- I-
why does cl have more negative electron gain enthalpy than F ?
first ionisation energy is lowest in :
rncarbon, lead,silicon or tin ???
The order of first electron affinity of O , S and Se :-
(A) O>S>Se (B) S>Se>O (C) Se>O>S (D) S>O>Se
which is the largest element in the periodic table? why?
Why group 1 elements are called alkali metals?
Why Group 2 elements are called alkali earth metals?
nitroge has positive electron gain enthalpy whereas oxygen has negative,however oxygen has lower ionization enthalpy than nitrogen.explain.
Arrange the following ions in the order of increasing size.
Be2+, Cl- ,S2- ,Na+, Mg2+,Br-
Also please explain why?
why is second ionization enthalpy greater than first ionization enthalpy?pls.explain
why group 17 elements called halogens...
The first member of the lanthanide series is lanthanum . True / False
Electron gain enthalpy of Oxygen and Fluorine is less negative than suceeding element S and Cl. Why?
What is Covalency?How to find the covalency of any element
1. Li , Be , B , C , N , O , F , Ne
2. Na , Mg , Al , Si , P , S , Cl , Ar
neon has got more atomic radius than flourine.How?
Explain why halogens have maximum electron gain enthalpy in their respective periods.
what are typical elements and how do they differ from transision elements
what is mean by unpaired electron.........?? pls explain with examples
FULL FORM OF METAL
elements of IB and II B are called
a- normal elements
b- transition element
c- alkaline earth metals
d- alkali metals
CH4 , H2O , NH3 order of increasing bond angle around central atom
what is dsp 2 hybridization
How does atomic radius vary in a period and in a group ? How yoy explain the variation ?
increasing order of atomic radii of the elements B, Al, C, Si, is
a- si, al, c, b
b- B, C, Al,Si,
c- Al, Si, B, C
D- C, B, Si, Al
how to calculate covalency?
how we can learn periodic table fast n easily ????????plz give me ur suggstions frzzzzz
Q.(c) What is electronegativity? Explain why halogens possess highest electronegativity.
the first ionisation energy of nitrogen is greater then that of oxygen , whereas the second ionisation energy of oxygen is greater than nitrogen....WHY..??????
Alkali metals have largest atomic volume in their period--is this true?