What is the total number of moles of H2SO4 needed to prepare 5.0 L at a 2.0M solution of H2SO4 ?
2.5
5.0
10
20
How many joules of heat are absorbed when 70.0 g of water is completely vaporised at its boiling point ?
23, 352
7,000
15,813
158, 130
D.
158, 130
Since the process involves phase change, heat absorbed,
Q = mass × latent heat of vaporisation
Given, mass = 70.0 g = 0.07 kg
Lv = 2260 kJ/ kg
Q = 0.07 × 2260 kJ
= 158. 2 kJ
= 158200 J.
In any chemical reaction, a quantity that decrease to a minimum is
free energy
entropy
temperature
enthalpy
Decrease in atomic number is not observed during
β- emission
α- emission
positron emission
electron capture
Which of the following will increase with the increase in temperature ?
Surface tension
Viscosity
Molality
Vapour pressure
The electron configuration of the oxide ion is much most similar to the electron configuration of the
sulphide ion
nitride ion
oxygen atom
nitrogen atom