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
The purity of a solid sample can best be determined by its
boiling point
melting point
conductivity
solubility
Correct answer is B
The purity of a solid can be determined by measuring the melting point. A pure solid will have a single, sharp melting point.
The seperation of Nitrogen from oxygen using fractional distillation of air is possible because
nitrogen is less dense than oxygen
oxygen is more reactive than nitrogen
of the difference in their boiling points
they belong to the same period
Correct answer is C
The various gases vaporize as their boiling points are reached, then they are pumped away and separately re-liquefied for convenient storage.