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- State one use of each of the following radioactive isotopes.
i)Cobalt – 60
ii)Phosphorus – 32 (Solved)
State one use of each of the following radioactive isotopes.
i)Cobalt – 60
ii)Phosphorus – 32
Date posted: October 31, 2019. Answers (1)
- The graph below shows the changes in viscosity in liquid sulphur on heating. Use it to answer the questions that follow.
Explain what happens in the...(Solved)
The graph below shows the changes in viscosity in liquid sulphur on heating. Use it to answer the questions that follow.
Explain what happens in the region:
i)XY
ii)YZ
Date posted: October 31, 2019. Answers (1)
- A sample of 0.5g of gaseous alkane occupied a volume of 200cm3 at s.t.p.
a)Determine the molar mass of the alkane.(C = 12.0, H = 1.0,...(Solved)
A sample of 0.5g of gaseous alkane occupied a volume of 200cm3 at s.t.p.
a)Determine the molar mass of the alkane.(C = 12.0, H = 1.0, Molar gas volume = 22.4dm3)
b)Determine the molecular formula of the alkane and give its I.U.PA.C name.
Date posted: October 31, 2019. Answers (1)
- Study the table below and complete the property column.(Solved)
Study the table below and complete the property column.
Date posted: October 31, 2019. Answers (1)
- Consider the following standard electrode potentials:(Solved)
Consider the following standard electrode potentials:
Some modern cars are made from steel coated with other metals. Using this data above state and explain the best suited metal for coating steel
Date posted: October 31, 2019. Answers (1)
- Calculate the mass of metal J that would be dissolved at the anode when a solution of J (III) nitrite is electrolysed using a current...(Solved)
Calculate the mass of metal J that would be dissolved at the anode when a solution of J (III) nitrite is electrolysed using a current of 1.5amperes for 15minutes (1 Faraday = 96,500C; J = 52)
Date posted: October 31, 2019. Answers (1)
- The following are standard reduction potentials;(Solved)
The following are standard reduction potentials;
Rewrite the 
values of the above half-cells using iron as a reference electrode
Date posted: October 31, 2019. Answers (1)
- Complete the following redox equations by adding the correct number of electrons on either
reactant or product side of the redox equations:-(Solved)
Complete the following redox equations by adding the correct number of electrons on either
reactant or product side of the redox equations:-
Date posted: October 31, 2019. Answers (1)
- The following diagram represents the electrolysis of dilute sodium chloride solution using inert
electrodes(Solved)
The following diagram represents the electrolysis of dilute sodium chloride solution using inert
electrodes
Determine the electrode at which different electrolytic products would be produced if the solution is electrolysed for several hours. Explain
Date posted: October 31, 2019. Answers (1)
- Use the cell representation below to answer the questions that follow:-(Solved)
Use the cell representation below to answer the questions that follow:-
X(s) /X3+(aq) //W2+(aq) /W(s)
(a) Write the equation for the cell reaction above
(b) If the e.m.f of the cell is 0.30V and value for W2+/W is -0.44volts, calculate the for X3+(aq) /X(s)
Date posted: October 31, 2019. Answers (1)
- Name two types of isotopes of phosphorous(Solved)
Name two types of isotopes of phosphorous
Date posted: October 31, 2019. Answers (1)
- The following are electrode potentials of the half cells(Solved)
The following are electrode potentials of the half cells
Calculate the potential difference of the following cell.
Date posted: October 31, 2019. Answers (1)
- The standard hydrogen electrode is used as the reference electrode. Some of the difficulties in using hydrogen gas as an electrode are:(Solved)
The standard hydrogen electrode is used as the reference electrode. Some of the difficulties in using hydrogen gas as an electrode are:
- Hydrogen is a gas at 25oC
- Hydrogen does not conduct electricity
-The half-cell reaction,
is slow and takes long to reach equilibrium.
Explain how these difficulties are solved in the standard hydrogen electrode
Date posted: October 31, 2019. Answers (1)
- The oxides of calcium and phosphorous react as shown below:-(Solved)
The oxides of calcium and phosphorous react as shown below:-
6CaO(s) + P4O10(s)--------->2Ca3(PO4)2(s)
(i) Give a reason why these substances react and yet both are oxides
(ii) Work out the oxidation state of phosphorous in P4O10
(iii) State one use of Ca3(PO4)2
Date posted: October 31, 2019. Answers (1)
- Explain how the pollution caused by large scale extraction of Zinc can be reduced by having a fertilizer plant close to it.(Solved)
Explain how the pollution caused by large scale extraction of Zinc can be reduced by having a fertilizer plant close to it.
Date posted: October 31, 2019. Answers (1)
- Give the chemical formula of Zinc blende(Solved)
Give the chemical formula of Zinc blende
Date posted: October 31, 2019. Answers (1)
- The following is an equation for the reaction between ammonia and water(Solved)
The following is an equation for the reaction between ammonia and water
Name the base in the backward reaction
Date posted: October 31, 2019. Answers (1)
- Calculate the volume at s.t.p of hydrogen evolved when 2A of electricity are passed
through dilute sulphuric acid for 2hours.
(Molar gas volume at s.t.p = 22.4dm3,...(Solved)
Calculate the volume at s.t.p of hydrogen evolved when 2A of electricity are passed
through dilute sulphuric acid for 2hours.
(Molar gas volume at s.t.p = 22.4dm3, one Faraday= 96500coulombs)
Date posted: October 31, 2019. Answers (1)
- State Faradays First Law of Electrolysis(Solved)
State Faradays First Law of Electrolysis
Date posted: October 31, 2019. Answers (1)
- Copper (II) sulphate solution was electrolysed using copper electrode. A Current of 0.5A was passed for 64.3 minutes and a mass of 0.64g of copper...(Solved)
Copper (II) sulphate solution was electrolysed using copper electrode. A Current of 0.5A was
passed for 64.3 minutes and a mass of 0.64g of copper was deposited. (Cu = 63.5)
a) Which electrode decreased in mass during electrolysis? Explain
b) Calculate the quantity of charge needed to deposits 1 mole of copper
Date posted: October 31, 2019. Answers (1)