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Na ClO3: Because oxidation number of chlorine increases from 0 to +5
johnmulu answered the question on February 10, 2017 at 12:48
- The following two tests were carried out on chlorine water contained in two test-tubes(Solved)
The following two tests were carried out on chlorine water contained in two test-tubes:
a) A piece of blue flower was dropped into the first test-tube. Explain why the flower ached.
b) The second test-tube was corked and exposed to sunlight. After a few days, it was found to contain a gas that rekindled a glowing splint. Write an equation for the reaction which produced theas.
Date posted: February 10, 2017. Answers (1)
- Give the name of reagent which when reacted with concentrated hydrochloric acid produce chlorine gas(Solved)
Give the name of reagent which when reacted with concentrated hydrochloric acid produce chlorine gas.
Date posted: February 10, 2017. Answers (1)
- A sample of hydrogen chlorine was dissolved in water to make 250 cm3 of solution 25 cm3 of the solution required(Solved)
A sample of hydrogen chlorine was dissolved in water to make 250 cm3 of solution 25 cm3 of the solution required 46 cm3 of 11.0 M sodium hydroxide for complete neutralization
i) Calculate the number of moles of hydrochloric acid in 25 cm3 of solution
ii) Determine the mass of hydrogen chloride that was dissolved to make 250 cm3 of solution (Cl = 35.5, H = 1.0)
Date posted: February 7, 2017. Answers (1)
- The equation below represents a redox reaction (a) a) write down the equation for the reduction process(Solved)
The equation below represents a redox reaction.
Mg(s) + 2HCl(aq) $\rightarrow$ MgCl2(aq) + H2(g)
a) write down the equation for the reduction process
b) which substance is oxidized
Date posted: February 7, 2017. Answers (1)
- The equation below represents a redox reaction(Solved)
The equation below represents a redox reaction.
2FeCl2(aq) + Cl2(g) $\rightarrow$ 2FeCl3(aq)
Identify the reducing agent. Give reason.
Date posted: February 7, 2017. Answers (1)
- Chlorine and iodine are elements in the same group in the periodic table. Chlorine gas is yellow while aqueous, iodine, I2(aq) is brown(Solved)
Chlorine and iodine are elements in the same group in the periodic table. Chlorine gas is yellow while aqueous, iodine, I2(aq) is brown
a) What observation would be made if chlorine gas is bubbled through aqueous sodium iodine? Explain using an ionic equation
b) Under certain conditions chlorine and iodine react to give iodine trichloride, ICl3(s). What type of bonding would you expect to exist in iodine trichloride? Explain
Date posted: February 7, 2017. Answers (1)
- Calculate the mass of product that would be formed when 200 cm3 of hydrogen chloride gas reacts completely with excess ammonia gas(Solved)
Calculate the mass of product that would be formed when 200 cm3 of hydrogen chloride gas reacts completely with excess ammonia gas. (H = 1.0, N = 14.0, Cl = 35.5, one mole of gas occupies 24 litres at room temperatures and pressure)
Date posted: February 7, 2017. Answers (1)
- a) One of the allotropes of sulphur is rhombic sulphur, name the other allotrope b) Concentrated sulphuric (VI) acid reacts with ethanol and copper.(Solved)
a) One of the allotropes of sulphur is rhombic sulphur, name the other allotrope
b) Concentrated sulphuric (VI) acid reacts with ethanol and copper.
State the property of the acid shown in each case.
i) Ethanol
ii) Copper
Date posted: February 7, 2017. Answers (1)
- In the contact process, during the production of sulphur (VI) oxide, a catalyst is used(Solved)
In the contact process, during the production of sulphur (VI) oxide, a catalyst is used. Give two reasons why Vanadium (V) oxide is preferred to platinum
Date posted: February 7, 2017. Answers (1)
- In an experiment, sulphur (IV) oxide was dissolved in water to form solution L. (i) What would be observed if a few drops of barium nitrate solution were immediately added to solution L?(Solved)
In an experiment, sulphur (IV) oxide was dissolved in water to form solution L.
i) What would be observed if a few drops of barium nitrate solution were immediately added to solution L?
ii) Write an ionic equation for the reaction that occurred between solution L and aqueous barium nitrate in (i) above.
Date posted: February 7, 2017. Answers (1)
- What would be observed if sulphur (IV) oxide is bubbled through acidified potassium manganate (VII)?(Solved)
What would be observed if sulphur (IV) oxide is bubbled through acidified potassium manganate (VII)?
Date posted: February 7, 2017. Answers (1)
- Acidified potassium manganate (VII) solution is delocourised when sulphur (VI) oxide is bubbled through it. The equation for the reaction is given below(Solved)
Acidified potassium manganate (VII) solution is delocourised when sulphur (VI) oxide is bubbled through it. The equation for the reaction is given below
$2H_2O(l) + 5SO_2(g) + 2KMnO_4(aq) \rightarrow K_2SO_4(aq) + 2MnSO_4(aq) + 2H_2SO_4(aq)$
a) Which reactant is oxidized? Explain
b) Other than the manufacture of sulphuric (IV) acid, state one other use of Sulphur (IV) oxide
Date posted: February 7, 2017. Answers (1)
- Name two reagents that can be used to prepare hydrogen sulphide in the laboratory(Solved)
Name two reagents that can be used to prepare hydrogen sulphide in the laboratory
Date posted: February 7, 2017. Answers (1)
- Crude oil contains sulphur. What would be effect to the environment of using fuel containing sulphur?(Solved)
Crude oil contains sulphur. What would be effect to the environment of using fuel containing sulphur?
Date posted: February 7, 2017. Answers (1)
- State the observation made at the end of the experiment when a mixture of iron powder and sulphur is heated in a test tube (Solved)
a) State the observation made at the end of the experiment when a mixture of iron powder and sulphur is heated in a test tube
b) When a mixture of iron powder and sulphur is heated, it glows more brightly than that of iron fillings and sulphur. Explain this observation
Date posted: February 7, 2017. Answers (1)
- Suggest a reason why BaSO4 (A pigment made from sulphuric (VI) acid would be suitable in making paint for cars)(Solved)
Suggest a reason why BaSO4 (A pigment made from sulphuric (VI) acid would be suitable in making paint for cars)
Date posted: February 7, 2017. Answers (1)
- Name one fertilizer made from sulphuric (IV) acid(Solved)
Name one fertilizer made from sulphuric (IV) acid.
Date posted: February 7, 2017. Answers (1)
- When hydrogen sulphide gas was bubbled into an aqueous solution of iron (III) chloride, a yellow precipitate was deposited.(Solved)
When hydrogen sulphide gas was bubbled into an aqueous solution of iron (III) chloride, a yellow precipitate was deposited.
a) State another observation made
b) Write an equation for the reaction that took place
c) What type reaction was undergone by hydrogen sulphide in this reaction?
Date posted: February 7, 2017. Answers (1)
- In an experiment to study the properties of concentrated sulphuric (IV) acid, a mixture of the acid and wood charcoal was heated in a boiling tube(Solved)
In an experiment to study the properties of concentrated sulphuric (IV) acid, a mixture of the acid and wood charcoal was heated in a boiling tube.
a) Write the equation of the reaction that took place in the boiling tube
b) Using oxidation numbers, show that reduction and oxidation reactions took place in the boiling tube.
Date posted: February 7, 2017. Answers (1)
- In an experiment, a gas jar containing moist sulphur (IV) oxide was inverted over another gas jar containing hydrogen sulphide gas.(Solved)
In an experiment, a gas jar containing moist sulphur (IV) oxide was inverted over another gas jar containing hydrogen sulphide gas.
a) state and explain the observation that was made
b) state the precaution that should be taken when carrying out this experiment
Date posted: February 7, 2017. Answers (1)