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Starting with solid lead (II) carbonate, briefly describe how a sample of lead (II) chloride can be prepared.
(Solved)
Starting with solid lead (II) carbonate, briefly describe how a sample of lead (II) chloride can be prepared.
Date posted:
March 28, 2019
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Answers (1)
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a) Explain why hydrogen gas has been replaced by helium in filling aeroplane tyres.
b)Hydrogen gas is bubbled through oil in presence of a catalyst to...
(Solved)
a) Explain why hydrogen gas has been replaced by helium in filling aeroplane tyres.
b)Hydrogen gas is bubbled through oil in presence of a catalyst to yield fats.
(i) Name a suitable catalyst used in the above process.
(ii) What name is given to the above process.
Date posted:
March 28, 2019
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Answers (1)
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4. 9 g a tribasic acid was dissolved in water and the solution made up to 500cm3. If the molarity of the hydrogen ions in...
(Solved)
4. 9 g a tribasic acid was dissolved in water and the solution made up to 500cm3. If the molarity of the hydrogen ions in the solution is 0.3 molar calculate the relative molecular mass of the acid.
Date posted:
March 28, 2019
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Answers (1)
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The diagram below represents pipes used in Frasch pump for the extraction of sulpur
Name the substance that pass through the following tubes and the direction...
(Solved)
The diagram below represents pipes used in Frasch pump for the extraction of sulpur
Name the substance that pass through the following tubes and the direction which they flow.
1.
2.
3.
Date posted:
March 28, 2019
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Answers (1)
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12.0 cm3 of methane and 48cm3 of oxygen were exploded together. The final volume measured under the original conditions was 36.0 cm3 neglecting the water...
(Solved)
12.0 cm3 of methane and 48cm3 of oxygen were exploded together. The final volume measured under the original conditions was 36.0 cm3 neglecting the water formed. 24.0cm3 of this was unused oxygen. Show the ratio of reacting volume of the gases referred to and gaseous products formed.
Date posted:
March 28, 2019
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Answers (1)
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Element X contains isotopes with mass number 16 and 18 respectively existing in the ratio
1: 3. Calculate the relative atomic mass of X.
(Solved)
Element X contains isotopes with mass number 16 and 18 respectively existing in the ratio
1: 3. Calculate the relative atomic mass of X.
Date posted:
March 28, 2019
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Answers (1)
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What volume of methane would remain if a burner containing 40cm³ of methane burns in 40cm³ of enclosed air
(assuming that oxygen is 20% of air)?
(Solved)
What volume of methane would remain if a burner containing 40cm³ of methane burns in 40cm³ of enclosed air
(assuming that oxygen is 20% of air)?
Date posted:
March 28, 2019
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Answers (1)
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A compound has empirical formula C3H6O and relative formula mass of 116. Determine it’s molecular formula.(C = 12, H = 1, O = 16).
(Solved)
A compound has empirical formula C3H6O and relative formula mass of 116. Determine it’s molecular formula.(C = 12, H = 1, O = 16).
Date posted:
March 28, 2019
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Answers (1)
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The scheme below shows some reaction of salt. Study it and answer questions that follow.
(Solved)
The scheme below shows some reaction of salt. Study it and answer questions that follow.
(i) Write an equation for the reaction to show formation of gas P and solid X.
(ii) Give the name and formula of the complex ion responsible for the deep blue colour in the solution.
Date posted:
March 28, 2019
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Answers (1)
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Explain why potassium chloride conducts electricity in both the molten state and in aqueous solution whereas hydrogen chloride conducts electricity only in aqueous solution and...
(Solved)
Explain why potassium chloride conducts electricity in both the molten state and in aqueous solution whereas hydrogen chloride conducts electricity only in aqueous solution and not in gaseous state.
Date posted:
March 28, 2019
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Answers (1)
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An element E has relative atomic mass of 69.39. Given that the element has two isotopes of atomic masses 62.35 and 70.45, calculate the relative...
(Solved)
An element E has relative atomic mass of 69.39. Given that the element has two isotopes of atomic masses 62.35 and 70.45, calculate the relative abundance of each of the isotopes.
Date posted:
March 28, 2019
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Answers (1)
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Name the method of separation that can most suitably be used to separate the following mixtures.
(a) Gasoline from petroleum
(b) Benzoic acid and potassium carbonate
(c) Oil...
(Solved)
Name the method of separation that can most suitably be used to separate the following mixtures.
(a) Gasoline from petroleum
(b) Benzoic acid and potassium carbonate
(c) Oil from cashew nuts
Date posted:
March 28, 2019
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Answers (1)
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25.0cm3 of 0.12M potassium hydroxide solution required 30.0cm3 of a solution of a dibasic acid (H2Y) for complete neutralization. The acid contained 3.15g per 500cm3...
(Solved)
25.0cm3 of 0.12M potassium hydroxide solution required 30.0cm3 of a solution of a dibasic acid (H2Y) for complete neutralization. The acid contained 3.15g per 500cm3 solution.
Calculate:
(a) The molarity of the acid solution
(b) The relative formula mass of the acid.
Date posted:
March 28, 2019
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Answers (1)
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A Student in form four placed a thermometer in molten naphthalene at 850C and recorded the temperature and time until the naphthalene solidified. From the...
(Solved)
A Student in form four placed a thermometer in molten naphthalene at 850C and recorded the temperature and time until the naphthalene solidified. From the values obtained, the figure below was drawn.
(a) What name is given to such a figure?
(b) Which part of the figure represents the change of state of naphthalene?
(c)In terms of kinetic theory. Explain what happens to molecules along AB.
Date posted:
March 28, 2019
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Answers (1)
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The table below shows information about three solid substances A, B and C. Study it and answer the question that follow.
Describe how you will separate...
(Solved)
The table below shows information about three solid substances A, B and C. Study it and answer the question that follow.
Describe how you will separate the three solids from a mixture of the three.
Date posted:
March 28, 2019
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Answers (1)
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Calculate the volume of carbon (IV) oxide that would be produced if 15g of calcium carbonate reacted with 100cm³ of 2.0M hydrochloric acid (C =...
(Solved)
Calculate the volume of carbon (IV) oxide that would be produced if 15g of calcium carbonate reacted with 100cm³ of 2.0M hydrochloric acid (C = 12.0, O = 16.0, Ca = 40.0) molar gas volume = 24000cm³
Date posted:
March 28, 2019
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Answers (1)
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When lead (II) Carbonate is reacted with dilute sulphuric (VI) acid, the reaction takes place for a short time and then stops. Explain.
(Solved)
When lead (II) Carbonate is reacted with dilute sulphuric (VI) acid, the reaction takes place for a short time and then stops. Explain.
Date posted:
March 28, 2019
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Answers (1)
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Name the particles responsible for the electrical conductivity of:
(a) Graphite
(b) Magnesium Sulphate solution
(Solved)
Name the particles responsible for the electrical conductivity of:
(a) Graphite
(b) Magnesium Sulphate solution
Date posted:
March 28, 2019
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Answers (1)
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It is advisable to leave your flame in the luminous state when not in use. Give a reason why.
(Solved)
It is advisable to leave your flame in the luminous state when not in use. Give a reason why.
Date posted:
March 28, 2019
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Answers (1)
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The diagram below shows a non-luminous flame. Use it to answer the questions that follow:
(Solved)
The diagram below shows a non-luminous flame. Use it to answer the questions that follow:
Two wooden splints were placed across regions X and Y respectively. Draw labelled diagrams to show the effects observed on the wooden splint placed across each region.
(i) Region X.
(ii) Region Y.
Date posted:
March 28, 2019
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Answers (1)