- A small crystal of potassium manganate (VII) was placed in a beaker containing water. The beaker was left standing for two days without shaking.(Solved)
A small crystal of potassium manganate (VII) was placed in a beaker containing water. The beaker was left standing for two days without shaking. State and explain the observation that were made
Date posted: February 3, 2017.
- State the Charles’ law(Solved)
State the Charles’ law.
Date posted: February 3, 2017.
- A few crystals of crystals of potassium manganite (VII) were carefully placed into water in a beaker at one spot(Solved)
A few crystals of crystals of potassium manganite (VII) were carefully placed into water in a beaker at one spot. The beaker was left undisturbed for two hours. State and explain the observations.
Date posted: February 3, 2017.
- In an experiment, ammonium chloride was heated in a test-tube. A moist red litmus paper placed at the mouth of the test tube(Solved)
In an experiment, ammonium chloride was heated in a test-tube. A moist red litmus paper placed at the mouth of the test tube first changed blue then red. Explain these observations
Date posted: February 3, 2017.
- Charcoal is a fuel that is commonly used for cooking. When it burns it forms two oxides(Solved)
Charcoal is a fuel that is commonly used for cooking. When it burns it forms two oxides
a) Name the two oxides
b) State one use of the two oxide
Date posted: February 3, 2017.
- What is the role of carbon (IV) oxide in fire extinguishing?(Solved)
What is the role of carbon (IV) oxide in fire extinguishing?
Date posted: February 3, 2017.
- Describe how carbon (IV) oxide can be distinguished from carbon (II) oxide using calcium hydroxide solution(Solved)
Describe how carbon (IV) oxide can be distinguished from carbon (II) oxide using calcium hydroxide solution
Date posted: February 3, 2017.
- Diamond and graphite are allotropes of carbon. What is meant by an allotrope (Solved)
a) Diamond and graphite are allotropes of carbon. What is meant by an allotrope
b) Explain why graphite can be used as a lubricant while diamond cannot
Date posted: February 3, 2017.
- Graphite is one of the allotropes of carbon (a) Name one other element which exhibits allotropy(Solved)
Graphite is one of the allotropes of carbon
a) Name one other element which exhibits allotropy
b) Explain why graphite is used in the making of pencil leads
Date posted: February 3, 2017.
- State and explain one chemical property that makes carbon (II) oxide poisonous to human beings(Solved)
State and explain one chemical property that makes carbon (II) oxide poisonous to human beings.
Date posted: February 3, 2017.
- Carbon (II) oxide is describe as “a silent killer”.
(a) State one physical property of carbon (II) oxide that makes it “a silent killer”
(b) Write...(Solved)
Carbon (II) oxide is describe as “a silent killer”.
(a) State one physical property of carbon (II) oxide that makes it “a silent killer”.
(b) Write the formula of the oxide of carbon which is "silent killer".
Date posted: February 3, 2017.
- In terms of structure and bonding, explain why graphite is used as a lubricant(Solved)
In terms of structure and bonding, explain why graphite is used as a lubricant.
Date posted: February 3, 2017.
- Explain why diamond is hard while graphite is soft(Solved)
Both diamond and graphite have giant atomic structures. Explain why diamond is hard while graphite is soft
Date posted: February 3, 2017.
- Explain why burning magnesium continues to burn in a gas jar containing sulphur (IV) oxide while a burning splint is extinguished(Solved)
Explain why burning magnesium continues to burn in a gas jar containing sulphur (IV) oxide while a burning splint is extinguished.
Date posted: February 3, 2017.
- State and explain the function of tartaric acid in baking powder(Solved)
State and explain the function of tartaric acid in baking powder.
Date posted: February 3, 2017.
- Why is it not advisable to leave a Jiko with burning charcoal in closed room where one is sleeping?(Solved)
Explain why it is not advisable to leave a Jiko with burning charcoal in closed room where one is sleeping.
Date posted: February 3, 2017.
- Explain why carbon (IV) oxide is used in preference to water when extinguishing a fire caused by burning kerosene(Solved)
When extinguishing a fire caused by burning kerosene, carbon (IV) oxide is used in preference to water. Explain
Date posted: February 3, 2017.
- Write an equation for the reaction that takes place when carbon (II) oxide gas is passed over heated lead (II) oxide (Solved)
Write an equation for the reaction that takes place when carbon (II) oxide gas is passed over heated lead (II) oxide.
Date posted: February 3, 2017.
- Give reason why calcium hydroxide solution is used to detect the presence of carbon (IV) oxide gas while sodium hydroxide is NOT (Solved)
Give reason why calcium hydroxide solution is used to detect the presence of carbon (IV) oxide gas while sodium hydroxide is NOT.
Date posted: February 3, 2017.
- Explain how conduction of electricity takes place in the following(Solved)
Explain how conduction of electricity takes place in the following:
a) Iron metal
b) Molten lead (II) iodide
Date posted: February 3, 2017.
- Charcoal is a fuel that is commonly used in cooking. When it burns it forms two oxides(Solved)
Charcoal is a fuel that is commonly used in cooking. When it burns it forms two oxides
a) Name the two oxides
b) State one use of the two oxides
Date posted: February 3, 2017.
- Explain why the following substances conduct an electric current(Solved)
Explain why the following substances conduct an electric current
a) Magnesium metal
b) Molten magnesium chloride
Date posted: February 3, 2017.
- Starting with barium nitrate solution, describe how a pure sample of barium carbonate can be prepared in the laboratory(Solved)
Starting with barium nitrate solution, describe how a pure sample of barium carbonate can be prepared in the laboratory.
Date posted: February 3, 2017.
- Describe how a pure sample of lead (II) sulphate can be prepared in the laboratory starting with lead metal(Solved)
Describe how a pure sample of lead (II) sulphate can be prepared in the laboratory starting with lead metal
Date posted: February 3, 2017.
- Describe one method that can be used to distinguish between sodium sulphate and sodium hydrogen sulphate(Solved)
Describe one method that can be used to distinguish between sodium sulphate and sodium hydrogen sulphate.
Date posted: February 3, 2017.
- Distinguish between the terms deliquescent and efflorescent as used in chemistry(Solved)
Distinguish between the terms deliquescent and efflorescent as used in chemistry.
Date posted: February 2, 2017.
- Describe how a solid sample of the double salt, ammonium iron (II) sulphate, can be prepared using the following reagents(Solved)
Describe how a solid sample of the double salt, ammonium iron (II) sulphate, can be prepared using the following reagents: Aqueous ammonia, sulphuric (VI) acid and iron metal
Date posted: February 2, 2017.
- Distinguish between a deliquescent and hygroscopic substance (Solved)
Distinguish between a deliquescent and hygroscopic substance.
Date posted: February 2, 2017.
- Starting with sodium metal, describe how a sample of crystals of sodium hydrogen carbonate may be prepared(Solved)
Starting with sodium metal, describe how a sample of crystals of sodium hydrogen carbonate may be prepared.
Date posted: February 2, 2017.
- Starting with copper metal, describe how a sample of crystals of sodium hydrogen carbonate may be prepared in laboratory(Solved)
Starting with copper metal, describe how a sample of crystals of sodium hydrogen carbonate may be prepared in laboratory.
Date posted: February 2, 2017.