If 117 gm NaCl is dissolved in 1000 g of water the concentration of the solution is said to be :
2 molar
2 molal
1 normal
1 molal
A solution of 4.5 g of a pure non-electrolyte in 100 g of water was found to freeze at 0.465°C. The molecular weight of the solute is closest to (kf =1.86)
180.0
135.0
172.0
90.0
Irrespective of the source, pure sample of water always yields 88.89% mass of oxygen and 11.11 % mass of hydrogen. This is explained by the law of;
conservation of mass
constant composition
multiple proportion
Gay-Lussa
Identify the incorrect statement :
The molarity of a solution is independent of temperature
The tendency for catenation is much higher for carbon than for silicon
Nitriles and iso nitriles constitute metamers
t-butyl 1-carbocation has planar carbons and is very reactive
A 5 molar solution of H2SO4 is diluted from 1 L to 10 L. What is the normality of the solution ?
0.25 N
1 N
2 N
7 N
If the heat of formation of CO2 is -393 kJ. The amount of heat evolved in the formation of 0.176 kg of CO2 is
-1357.9kJ
-1275.9kJ
-1572.0kJ
-1165.5kJ
C.
-1572.0kJ
Heat of formation is amount of heat absorbed or evolved when 1 mole of substance is formed from its elements.
Given, mass of CO2 = 0.176 kg = 176 g
Molecular weight of CO2 = 1 mole of
CO2 = 44 g
Heat evolved when 44 g of CO2 is produced = -393 kJ
Heat evolved when 176 g of CO2 is produced = .
In a nuclide, one a.m.u. of mass is dissipated into energy to bind its nucleons. The energy equivalent of this mass is
931.5 eV
931.5 × 106 eV
931.5 × 106 MeV
931.5 MV