Name the process which takes place when: (a) Solid carbon (IV) oxide (dry ice) changes directly into gas

Name the process which takes place when:
a) Solid carbon (IV) oxide (dry ice) changes directly into gas
b) A red litmus paper turns white when dropped into chlorine water.
c) Propene gas molecules are converted into a giant molecule

---

a) Sublimation

b) Bleaching

c) Polymerisation

---

johnmulu answered the question on February 10, 2017 at 12:52

Exams With Marking Schemes

• Grade 1
• Grade 2
• Grade 3
• Grade 4
• Grade 5
• Grade 6
• Grade 7
• Grade 8
• Grade 9
• PP1
• PP2
• Playgroup
• Form 1
• Form 2
• Form 3
• Form 4

Related Questions

---

• The reaction between hot concentrated sodium hydroxide and chlorine produces sodium chlorate (V), sodium chloride and water. (Solved)
  

  The reaction between hot concentrated sodium hydroxide and chlorine produces sodium chlorate (V), sodium chloride and water.
  a) Write the equation for the reaction
  b) Give one use of sodium chlorate (V)
  

  Date posted: February 10, 2017 .    Answers (1)

• Calcium oxide can be used to dry ammonia gas (a) Explain why calcium oxide is not used to dry hydrogen chloride gas (Solved)
  

  Calcium oxide can be used to dry ammonia gas.
  (a) Explain why calcium oxide is not used to dry hydrogen chloride gas
  (b) Name one drying agent for hydrogen chloride gas
  

  Date posted: February 10, 2017 .    Answers (1)

• When excess chlorine gas was bubbled into hot concentrated sodium hydroxide, the following reaction occurred (Solved)
  

  When excess chlorine gas was bubbled into hot concentrated sodium hydroxide, the following reaction occurred.
  
  3Cl₂(g) + 6NaOH(aq) $\rightarrow$ NaClO₃(aq) + 5NaCl(aq) + 3H₂O(l)
  In which product did chlorine undergo oxidation? Explain.
  

  Date posted: February 10, 2017 .    Answers (1)

• 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)