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Dark iodine crystals turn into purple vapour.
Belan answered the question on February 13, 2019 at 11:54
- Describe how a detergent functions in cleaning.(Solved)
Describe how a detergent functions in cleaning.
Date posted: February 13, 2019. Answers (1)
- State three factors that influence ionization energy.(Solved)
State three factors that influence ionization energy.
Date posted: February 13, 2019. Answers (1)
- Give three applications of calcium oxide.(Solved)
Give three applications of calcium oxide.
Date posted: February 13, 2019. Answers (1)
- 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. Answers (1)
- 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. Answers (1)
- What is the Avogadro's Constant?(Solved)
What is the Avogadro's Constant?
Date posted: February 5, 2019. Answers (1)
- Oxygen gas takes 250 seconds to diffuse through a porous diaphragm. Calculate the molar mass of gas Z which takes 227 second to diffuse.(Solved)
Oxygen gas takes 250 seconds to diffuse through a porous diaphragm. Calculate the molar mass of gas Z which takes 227 second to diffuse.
Date posted: February 5, 2019. Answers (1)
- How long would 200cm3 of Hydrogen chloride take to diffuse through a porous plug if carbon(IV)oxide takes 200seconds to diffuse through?(Solved)
How long would 200cm3 of Hydrogen chloride take to diffuse through a porous plug if carbon(IV)oxide takes 200seconds to diffuse through?
Date posted: February 5, 2019. Answers (1)
- It takes 30 seconds for 100cm3 of carbon(IV)oxide to diffuse across a porous plate. How long will it take 150cm3 of nitrogen(IV)oxide to diffuse across...(Solved)
It takes 30 seconds for 100cm3 of carbon(IV)oxide to diffuse across a porous plate. How long will it take 150cm3 of nitrogen(IV)oxide to diffuse across the same plate under the same conditions of temperature and pressure?
(C=12.0,N=14.0=16.0)
Date posted: February 5, 2019. Answers (1)
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State Grahams law of diffusion and show its mathematical formula
Date posted: February 5, 2019. Answers (1)
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State Charles law and show its mathematical formula
Date posted: February 5, 2019. Answers (1)
- Calculate the pressure which must be applied to a fixed mass of 100cm3 of Oxygen for its volume to triple at 100000Nm-2.(Solved)
Calculate the pressure which must be applied to a fixed mass of 100cm3 of Oxygen for its volume to triple at 100000Nm-2.
Date posted: February 5, 2019. Answers (1)
- A fixed mass of gas at 102300Pa pressure has a volume of 25cm3. Calculate its volume if the pressure is doubled.(Solved)
A fixed mass of gas at 102300Pa pressure has a volume of 25cm3. Calculate its volume if the pressure is doubled.
Date posted: February 5, 2019. Answers (1)
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State Boyles law and show its mathematical formula
Date posted: February 5, 2019. Answers (1)
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List two physical conditions that affect gas
Date posted: February 5, 2019. Answers (1)
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Date posted: February 5, 2019. Answers (1)
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What is the difference between circulated and uncirculated hydrocarbon?
Date posted: February 4, 2019. Answers (1)
- Two students A and B are taking milk using a straw. A is standing on top of a high mountain while B stands at the...(Solved)
Two students A and B are taking milk using a straw. A is standing on top of a high mountain while B stands at the foot of the mountain. State with a reason which student takes the milk more easily.
Date posted: January 21, 2019. Answers (1)
- If magnesium ribbon was used in place of calcium, explain why it was necessary to clean the magnesium with steel wool before its reaction with...(Solved)
If magnesium ribbon was used in place of calcium, explain why it was necessary to clean the magnesium with steel wool before its reaction with Water.
Date posted: January 21, 2019. Answers (1)
- Explain the observation that was made when a few drops of phenolphthalein indicator were added to the resulting solution.(Solved)
Explain the observation that was made when a few drops of phenolphthalein indicator were added to the resulting solution.
Date posted: January 21, 2019. Answers (1)