The first ionisation energy of silicon is lower than that of
A. Aluminium
B. carbon
C. potassium
D. calcium
1 Answers
Talk Doctor Online in Bissoy App
If 0.1 M of a weak monobasic acid is taken and its percentage degree of ionisation is `1.34 %`, then calculate its ionisation constant.
Correct Answer - B `alpha =1.34 %=(1.34)/(100)=1.34 xx 10^(-2)` `C=0.1 mol L^(-1)` `K_(a)=C alpha^(2) =0.1 xx (1.34 xx 10^(-2))^(2)` `=1.7956 xx 10^(-5)`
2 Answers 1 views
Assertion Nitrogen has higher first ionisation energy than oxygen. Reason Atomic radius of nitrogen is smaller than that of oxygen.
Correct Answer - C Correct reason : The configuration of N atom is more symmetrical than that of oxygen
2 Answers 2 views
Statement-I : Adamantine silicon is obtained by heating silica with aluminium. Statement-II : Adamantine silicon is an alloy of aluminium and silicon.
Correct Answer - C Reason: Adamantine is a purer form of silicon.
2 Answers 1 views
Assertion : Reduction potential of Mn ( + 3 to + 2) is more positive than that of Fe ( + 3 to + 2). Reason : Ionisation potential of Mn is more than t
Correct Answer - C (c) Correct reason. `Mn^(2+)" "(3d^(5))` has more stable configuration than `Mn^(3+)" "(3d^(4))` while `Fe^(3+)" "(3d^(5))` has more stable configuration than `Fe^(2+)" "(3d^(6))`. Therefore, `E_(Mn^(3+)//Mn^(2+))^(@)` couple is more...
2 Answers 3 views
Element which has minimum first ionisation energy is -
Correct Answer - D Order of `I^(st)` ionisation energy `N gt O gt P gt S`
2 Answers 1 views
The ionisation energy of hydrogen is 13.6 eV . The energy of the photon released when an electron jumps from the first excited state (n=2) to the grou
Correct Answer - C The energy rquired to removed electron in the first excited state (n=2) The energy of the photon `Rhc((1)/(1^(2))-(1)/(n^(2)))` `rArr" " 13.6((1)/(4)-(1)/(4))=13.6((4-1)/(4))` `" " =13.6 xx(3)/(4)=(40.8)/(4)=10.2eV`
2 Answers 1 views
Statement-1: Third ionisation energy of phosphorous is larger than sulphur. Statement-2: There is a larger amount of stability associated with filled
Correct Answer - D Statement-1 is false. Electrons configuration`._16S^(2+)=1s^2 2s^2 2p^6 3s^2 3p^2 and ._15P^(2+)=1s^2 2s^2 2p^6 3s^2 3p^1` Sulphur has higher nuclear charge and smaller size than that of phosphorus...
2 Answers 1 views
First and second ionisation energies of magnesium are `7.646 eV` and `15.035ev` respectively. The amount of energy in `kJ` needed to convert all the a
Total energy needed to convert one `Mg` atom into `Mg^(2+)` gas ion, `= IE_(I) +IE_(II) = 22.681 eV = 2188.6 kJ mol^(-1)` `rArr 12 mg of Mg = 0.5 xx...
2 Answers 1 views
Those elements impart colour to the flame on heating in it, the atoms of which require low energy for the ionisation (i.e. absorb energy in the visibl
Correct Answer - A::C Elements of Group 1 & 2 have low `IE` have. So they impart colour to flame. `E.g. Li, Na, K, Ca, Ba`, etc.
2 Answers 1 views
If the binding energy of `2^(nd)` excited state of a hydrogen like sample os `24 eV` approximately, then the ionisation energy of the sample is approx
Correct Answer - D `(13.6(Z)^(2))/((3)^(2))=24` I.E. `=13.6(Z)^(2)=(24xx9)=216 ev`
2 Answers 1 views