Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.
left and equilibrium constant decreases
left and equilibrium constant increases
right and equilibrium constant increases
right and equilibrium constant decreases
Correct answer is A
This is typical of what happens with any equilibrium where the forward reaction is exothermic. Increasing the temperature decreases the value of the equilibrium constant. Where the forward reaction is endothermic, increasing the temperature increases the value of the equilibrium constant. Endothermic reaction has a Positive Enthalpy change. Exothermic reaction has a negative enthalpy change.
3.30
13.00
10.70
11.30
Correct answer is A
PH+POH=14
p\(^{H}\) = Log [H\(^+\)]
p[H\(^+\) ] = 2.0 X 10\(^{-11}\)moldm\(^{-3}\)
p\(^{H}\) = Log [2.0 X 10\(^{-11}\)]
p\(^{H}\) = 10.70
10.70+ p\(^{OH}\) =14
p\(^{OH}\) = 14 -10.70
= 3.30
law of multiple proportions
law of chemical proportions
law of simple proportions
law of conservation of mass
Correct answer is A
The law of multiple proportion states that when element A and B combine to form more than one chemical compound then the various masses of sample A react with a fixed mass of sample B are in a simple multiple ratio.
The knowledge of half-life can be used to
Create an element
Detect an element
To combine elements
Irradiate an element
Correct answer is B
Half-life, in radioactivity, the interval of time required for one-half of the atomic nuclei of a radioactive sample to decay (change spontaneously into other nuclear species by emitting particles and energy), or, equivalently, the time interval required for the number of disintegrations per second of a radioactive material to decrease by one-half
The figure above shows the electrolysis of molten sodium chloride. Z is the
anode where the Cl\(^-\) ions are oxidized
cathode where the Cl\(^-\) ions are reduced
anode where the Na\(^+\) ions are reduced
cathode where the Na\(^+\) ions are oxidized
Correct answer is A
During the electrolysis of brine, the chlorine ions are discharged at the anode and are oxidized. While at the cathode Hydrogen ion is discharged.