CBSE
In III group precipitation, NH4Cl is added before adding NH4OH to
decrease conc. of OH-
prevent interference of PO
increase conc. of Cl-
increase conc. of OH- ion
When copper reacts with hot and conc. H2SO4 gives
H2
N2
O2
SO2
Which of the following is not correct ?
Hydrolysis of NCl3 gives NH3 and HOCl
NH3 is less stable than PH3
NH3 is a weak reducing reagent compared to PH3
Nitric oxide in solid state exhibits diamagnetic property
The set representing the correct order for first ionisation potential is
K > Na > Li
Be > Mg > Ca
B > C > N
Ge > Si > C
What will be the order of Ist ionisation energy?
Li > Na > K
K > Li > Na
Na > Li > K
Li > K > Na
BaO2 and ozone reacts to produce
Ba
Ba2O3
BaO
Ba(OH)3
The most stable compound is
LiF
LiCl
LiBr
LiI
Which of the following statement(s) is/are correct regarding shielding effect?
The magnitude of screening effect do not depends upon the number of inner electrons
The magnitude of effective nuclear charge decreases in a period.
Greater the shielding effect, lower will be the atomic radii
For a given 'orbit' the shielding effect of electron belonging to different subshell decrease in the order s > p > d >f
A nuclide of an alkaline earth metal undergoes radioactive decay by emission of three -particles in succession. The group of the periodic table to which the resulting daughter element would belong to
Group 14
Group 16
Group 4
Group 6
The first ionisation enthalpy of boron is less than beryllium because:
Boron has high nuclear charge
The size of boron atom is more than beryllium atom
p-subshell of boron has only one electron
The size cit boron atom is less than beryllium atom