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- 46.0g of a metal carbonate MCO3 was dissolved 160cm3 of 0.1M excess hydrochloric acid and the resultant solution diluted to one litre.25.0cm3 of this solution...(Solved)
46.0g of a metal carbonate MCO3 was dissolved 160cm3 of 0.1M excess hydrochloric acid and the resultant solution diluted to one litre.25.0cm3 of this solution required 20.0cm3 of 0.1M sodium hydroxide solution for
complete neutralization. Calculate the atomic mass of "M"
Date posted: February 18, 2019.
- A certain carbonate, GCO3, reacts with dilute hydrochloric acid according to the equation given below
If 1 g of the carbonate reacts completely with 20 cm3...(Solved)
A certain carbonate, GCO3, reacts with dilute hydrochloric acid according to the equation given below
If 1 g of the carbonate reacts completely with 20 cm3 of 1 M hydrochloric acid ,calculate the relative atomic mass of G (C = 12.0 = 16.0)
Date posted: February 18, 2019.
- 20.0cm3 of 0.05 M acidified potassium manganate(VII)solution oxidized 25.0cm3 of Fe2+(aq) ions in 40.0g/l of impure Iron (II)sulphate(VI) to Fe3+(aq) ions. Calculate the percentage impurities...(Solved)
20.0cm3 of 0.05 M acidified potassium manganate(VII)solution oxidized 25.0cm3 of Fe2+(aq) ions in 40.0g/l of impure Iron (II)sulphate(VI) to Fe3+(aq) ions. Calculate the percentage impurities in the Iron (II)sulphate(VI).
Date posted: February 18, 2019.
- You are provided with:
(i)sodium L containing 5.0g per litre of a dibasic organic acid H2X.2H2O.
(ii)solution M which is acidified potassium manganate(VII)
(iii)solution N a mixture of...(Solved)
You are provided with:
(i)sodium L containing 5.0g per litre of a dibasic organic acid H2X.2H2O.
(ii)solution M which is acidified potassium manganate(VII)
(iii)solution N a mixture of sodium ethanedioate and ethanedioic acid
(iv) 0.1M sodium hydroxide solution P
(v) 1.0M sulphuric(VI)
You are required to:
(i)standardize solution M using solution L
(ii)use standardized solution M and solution P to determine the % of sodium ethanedioate in the mixture
Date posted: February 18, 2019.
- You are provided with:
(i)an impure calcium carbonate labeled M
(ii)Hydrochloric acid labeled solution N
(iii)solution L containing 20g per litre sodium hydroxide(Solved)
You are provided with:
(i)an impure calcium carbonate labeled M
(ii)Hydrochloric acid labeled solution N
(iii)solution L containing 20g per litre sodium hydroxide
You are required to determine the concentration of N in moles per litre and the % of calcium carbonate in mixture M.
Date posted: February 18, 2019.
- You are provided with: Acidified Potassium Manganate (VII) solution A, 0.1M of an iron (II) salt solution B....
(Solved)
You are provided with:
Date posted: February 15, 2019.
- Calculate the molarity of a solution containing 4.0 g sodium hydroxide dissolved in 500 cm3 solution(Solved)
Calculate the molarity of a solution containing 4.0 g sodium hydroxide dissolved in 500 cm3 solution
Date posted: February 15, 2019.
- 100 cm3 of nitrogen (II)oxide NO combine with 50 cm3 of Oxygen to form 100 cm3 of a single gaseous compound of nitrogen. All volumes...(Solved)
100 cm3 of nitrogen (II)oxide NO combine with 50 cm3 of Oxygen to form 100 cm3 of a single gaseous compound of nitrogen. All volumes measured at the same temperature and pressure. Obtain the equation for the reaction and name the gaseous product
Date posted: February 15, 2019.
- 1.0g of an alloy of aluminium and copper were reacted with excess hydrochloric acid. If 840 cm3 of hydrogen at s.t.p was produced, calculate the...(Solved)
1.0g of an alloy of aluminium and copper were reacted with excess hydrochloric acid. If 840 cm3 of hydrogen at s.t.p was produced, calculate the % of copper in the alloy.(Al =27.0,one mole of a gas at s.t.p =22.4 dm3 )
Date posted: February 15, 2019.
- Calculate the volume of carbon(IV)oxide at r.t.p produced when 5.0 g of calcium carbonate is strongly heated.(Ca=40.0, C= 12.0,O = 16.0,1 mole of gas =22.4...(Solved)
Calculate the volume of carbon(IV)oxide at r.t.p produced when 5.0 g of calcium carbonate is strongly heated.(Ca=40.0, C= 12.0,O = 16.0,1 mole of gas =22.4 at r.t.p)
Date posted: February 15, 2019.
- Calculate the number of particles present in 0.135 g of a gaseous hydrocarbon X on complete combustion produces 0.41g of carbon(IV)oxide and 0.209g of water.0.29g...(Solved)
Calculate the number of particles present in 0.135 g of a gaseous hydrocarbon X on complete combustion produces 0.41g of carbon(IV)oxide and 0.209g of water.0.29g of X occupy 120cm3 at room temperature and 1 atmosphere pressure .Name X and draw its molecular structure.(C=12.0,O= 16.O,H=1.0,1 mole of gas occupies 24dm3 at r.t.p)
Date posted: February 15, 2019.
- A compound of carbon, hydrogen and oxygen contain 54.55% carbon, 9.09% and remaining 36.36% oxygen.
If its relative molecular mass is 88, determine its molecular formula(C=12.0,...(Solved)
A compound of carbon, hydrogen and oxygen contain 54.55% carbon, 9.09% and remaining 36.36% oxygen.
If its relative molecular mass is 88, determine its molecular formula(C=12.0, H =1.0, O= 16.0)
Date posted: February 15, 2019.
- A hydrocarbon was found to contain 92.3% carbon and the remaining Hydrogen. If the molecular mass of the compound is 78, determine the molecular formula(C=12.0,...(Solved)
A hydrocarbon was found to contain 92.3% carbon and the remaining Hydrogen. If the molecular mass of the compound is 78, determine the molecular formula(C=12.0, H =1.0)
Date posted: February 15, 2019.
- 1.60g of an oxide of Magnesium contain 0.84g by mass of Magnesium.
Determine its empirical formula(Mg = 24.0, 16.0)(Solved)
1.60g of an oxide of Magnesium contain 0.84g by mass of Magnesium.
Determine its empirical formula(Mg = 24.0, 16.0)
Date posted: February 15, 2019.
- Calculate the mass of Oxygen used to react with copper(Solved)
Calculate the mass of Oxygen used to react with copper
Date posted: February 15, 2019.
- 25 cm3 of carbon(II)oxide diffuses across a porous plate in 25 seconds. How long will it take 75 cm3 of Carbon(IV)oxide to diffuse across the...(Solved)
25 cm3 of carbon(II)oxide diffuses across a porous plate in 25 seconds. How long will it take 75 cm3 of Carbon(IV)oxide to diffuse across the same plate under the same conditions of temperature and pressure. (C=12.0,0=16.0)
Date posted: February 15, 2019.
- How long would 200 cm3 of Hydrogen chloride take to diffuse through a porous plug if carbon(IV)oxide takes 200 seconds to diffuse through?(Solved)
How long would 200 cm3 of Hydrogen chloride take to diffuse through a porous plug if carbon(IV)oxide takes 200 seconds to diffuse through?
Date posted: February 15, 2019.
- How does the use of manganese (IV) oxide in the laboratory preparation of chlorine gas differ from its use in the laboratory preparation of hydrogen...(Solved)
How does the use of manganese (IV) oxide in the laboratory preparation of chlorine gas differ from its use in the laboratory preparation of hydrogen gas?
Date posted: February 13, 2019.
- Explain the following:
(i)Nitric acid is stored in dark brown bottles.
(ii)Alkalis are not stored in Aluminium containers or bottles.(Solved)
Explain the following:
(i)Nitric acid is stored in dark brown bottles.
(ii)Alkalis are not stored in Aluminium containers or bottles.
Date posted: February 13, 2019.
- An element Q reacts with dilute acids but not with cold water. Element R does not react with dilute acids.Element S displaces element P from...(Solved)
An element Q reacts with dilute acids but not with cold water. Element R does not react with dilute acids. Element S displaces element P from its oxides. P reacts with cold water. Arrange the four metals in order of their reactivity starting with the most reactive.
Date posted: February 13, 2019.
- Give three uses of copper metal.(Solved)
Give three uses of copper metal.
Date posted: February 13, 2019.
- Define the term 'half life' as used in radioactivity.(Solved)
Define the term 'half life' as used in radioactivity.
Date posted: February 13, 2019.
- A form 1 student was supplied with a colourless liquid suspected to be water.
(i)Describe one chemical test that could be carried out to show that...(Solved)
A form 1 student was supplied with a colourless liquid suspected to be water.
(i)Describe one chemical test that could be carried out to show that the liquid was water.
(ii)How could it have been shown that the liquid was pure water?
Date posted: February 13, 2019.
- The use of materials of lead in roofing and in water pipes is being discouraged.
State
(i)Two reasons why these materials have been used in the past.
(ii)One...(Solved)
The use of materials of lead in roofing and in water pipes is being discouraged.
State
(i)Two reasons why these materials have been used in the past.
(ii)One reason why their use is being discouraged.
Date posted: February 13, 2019.
- State the observations made when iodine is heated in a boiling tube.(Solved)
State the observation made when iodine is heated in a boiling tube.
Date posted: February 13, 2019.
- Describe how a detergent functions in cleaning.(Solved)
Describe how a detergent functions in cleaning.
Date posted: February 13, 2019.
- State three factors that influence ionization energy.(Solved)
State three factors that influence ionization energy.
Date posted: February 13, 2019.
- Give three applications of calcium oxide.(Solved)
Give three applications of calcium oxide.
Date posted: February 13, 2019.
- An oxide of copper in a porcelain boat was reduced by a stream of hydrogen. The results obtained were as follows.
Mass of porcelain boat=4.5g
Mass of...(Solved)
An Oxide of copper in a porcelain boat was reduced by a stream of hydrogen. The results obtained were as follows.
Mass of porcelain boat=4.5g
Mass of boat + Oxide=6.40g
Mass of boat + Copper=6.02g
(i)Determine the empirical formula of the oxide.
(ii)If the relative formula mass of the oxide is 80,determine its chemical formula.
(Cu =64, O=16)
Date posted: February 13, 2019.
- Calculate the number of atoms present in:(Avogadros constant L = 6.0 x 10 23) 0.23 g of dilute sulphuric (VI)acid(Solved)
Calculate the number of atoms present in:(Avogadros constant L = 6.0 x 10 23) 0.23 g of dilute sulphuric (VI)acid
Date posted: February 5, 2019.