Which of the following correctly explains entropy?
the natural tendency for a system to achieve a greater disorder
a balance of two driving forces between free energy and enthalpy changes
the cause of spontaneity of a reaction
a measure of the enthalpy of a reaction
a measure of the rate of attaining equilibrum in a reversible reaction
Correct answer is A
No explanation has been provided for this answer.
1.2 x 10 23
3.0 x 1023
6.0 x1023
1.2 x 1024
30 x1023
Correct answer is B
mass of nitrogen gas = 14g, molar mass of nitrogen gas = 28gmol-1
mole = \(\frac{mass}{molar mass} = \frac{ no of particles }{ avogadro's no }\)
moles = \(\frac{14}{28} = \frac{ no of particles }{ 6.0 \times 10^{23}}\)
no of molecules = 0.5 x 6.0 x \(10^{23}\)
= 3.0 x \(10^{23}\)molecules.
A catayst which increases the rate of a chemical reaction does so by
increasing the reaction pathway
increasing the surface area of the reactants
increasing the pressure on the system
decreasing the temperature at which the reaction occurs
decreasing the activation energy of the reaction
Correct answer is E
No explanation has been provided for this answer.
Which of the following reactions does not occur in the blast furnace during the extraction of iron?
Fe2O3 (s) + 3CO(g) → 2Fe(l) + 3CO2(g)
C2 + CO 2(g)
CaO(s) + SiO2(s) → CaSiO 3(s)
FeO(s) + CO2(g) + Fe(l)
2Fe2O(s) → 4Fe(l) 3O2(g)
Correct answer is E
No explanation has been provided for this answer.
Which of the following compounds will undergo additional reactions?
Ethyne
Butane
Pentane
Tetrachloromethane
Ethanol
Correct answer is A
No explanation has been provided for this answer.