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- 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)
- State Grahams law of diffusion and show its mathematical formula(Solved)
State Grahams law of diffusion and show its mathematical formula
Date posted: February 5, 2019. Answers (1)
- State Charles law and show its mathematical formula(Solved)
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)
- State Boyles law and show its mathematical formula(Solved)
State Boyles law and show its mathematical formula
Date posted: February 5, 2019. Answers (1)
- List two physical conditions that affect gas(Solved)
List two physical conditions that affect gas
Date posted: February 5, 2019. Answers (1)
- List and explain the 3 forms of matter(Solved)
List and explain the 3 forms of matter
Date posted: February 5, 2019. Answers (1)
- What is the difference between circulated and uncirculated hydrocarbon?(Solved)
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)
- Magnesium and silicon are solids at room temperature, yet silicon has a higher melting point than magnesium(Solved)
Magnesium and silicon are solids at room temperature, yet silicon has a higher melting point than magnesium.
Date posted: January 21, 2019. Answers (1)
- How many atoms of each element are present in each of the following compounds? Lithium chloride(Solved)
How many atoms of each element are present in each of the following compounds? Lithium chloride
Date posted: January 7, 2019. Answers (1)
- All sulphates are soluble except two. Name them?(Solved)
All sulphates are soluble except two. Name them?
Date posted: January 5, 2019. Answers (1)
- Explain why bromine is a liquid at room temperature while chlorine is a gas(Solved)
Explain why bromine is a liquid at room temperature while chlorine is a gas
Date posted: January 3, 2019. Answers (1)
- Starting with zinc oxide, describe how you can prepare a sample of lead ii sulphate(Solved)
Starting with zinc oxide, describe how you can prepare a sample of lead ii sulphate
Date posted: January 2, 2019. Answers (1)
- In an experiment a piece of magnesium ribbon was cleaned with steel wool 2.4g of the clean ribbon was placed in a crucible and completely...(Solved)
In an experiment a piece of magnesium ribbon was cleaned with steel wool 2.4g of the clean ribbon was placed in a crucible and completely burnt in oxygen.after cooling the product weighted 4.0g.
(a)explain why it was necessary to clean the magnesium ribbon?
(b)what observation was made in the crucible after burning?
(c)why was there an increase in mass?
(d)write the equation for reaction which took place in the crucible?
(e)the product in the crucible was shaken with water and filtered. Explain the observation which was made when blue and red litmus papers were dropped into the filtrate.
Date posted: December 30, 2018. Answers (1)
- A student crushed the seeds and then added propane instead of water to extract oil from castor oil seeds. Why did he use propane instead...(Solved)
A student crushed the seeds and then added propane instead of water to extract oil from castor oil seeds. Why did he use propane instead of water and why were the seeds first crushed?
Date posted: December 26, 2018. Answers (1)
- Explain what is observed when ammonia gas is bubbled into copper sulphate solution till in excess(Solved)
Explain what is observed when ammonia gas is bubbled into copper sulphate solution till in excess
Date posted: December 20, 2018. Answers (1)