The oxidation number of nitrogen in \(Pb(NO_{3})_{2}\) is
+2
+3
+4
+5
Correct answer is D
\(Pb(NO_{3})_{2}\) = \(+2 +2N + (-2\times 6) = 0\)
= \(2N = 10\)
⇒ \(N = +5\)
The reason for the decrease in the atomic size of elements across a period is that
nuclear charge increases while the outermost electrons are drawn closer to the nucleus
nuclear charge decreases while the outermost electrons are drawn closer to the nucleus
valence electrons increase across the period while the valence shell remains constant
nuclear charge decreases while the distance of the valence shell from the nucleus is increasing
Correct answer is A
This is caused by the increase in the number of protons and electrons across a period.
The property of elements which increases down a group of the periodic table is
electronegativity
electron affinity
onic radius
ionization energy
Correct answer is C
The ionic radius decreases across a period but increases along a group.
the circular path through which electrons revolve round the nucleus
a region around the nucleus where electrons are most likely to be found
the path around the nucleus through which electrons move
the path around the nucleus through which protons move
Correct answer is B
The orbital is a path or region around the nucleus. The electrons move in the orbitals and not through it.
The mass of one mole of \((NH_{4})_{2}CO_{3}\) is [O=16.0, N=14.0, C=12.0, H=1.0]
66.0g
76.0g
80.0g
96.0g
Correct answer is D
This is same as asking for the molar mass of the compound
= \((2\times 14.0)+ (8\times 1.0) + 12.0+(16.0\times 3)\)
= 28.0+8.0+12.0+48.0 = 96.0g