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(a)phosporus has two allotropes and each has its own melting point
(b)It smoulders when exposed to air
isaacmuthini answered the question on October 6, 2017 at 11:09
- When lead nitrate and sodium sulphate react, a white precipitate is formed. (i)Identify the white precipitate.(ii) Write an ionic equation of the reaction(Solved)
When lead nitrate and sodium sulphate react, a white precipitate is formed. (i)Identify the white precipitate.(ii) Write an ionic equation of the reaction
Date posted: October 5, 2017. Answers (1)
- Starting with copper metal, describe how you can prepare solid copper (ii) carbonate(Solved)
Starting with copper metal, describe how you can prepare solid copper (ii) carbonate
Date posted: October 5, 2017. Answers (1)
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Date posted: October 4, 2017. Answers (1)
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Explain one way in which sulphur (IV) oxide is a pollutant
Date posted: October 4, 2017. Answers (1)
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The molar enthalpy of neutralisation between hydrochloric acid and ammonia solution was found to be -52.2 kj mol4, while that of hydrochloric acid and sodium hydroxide was 57.1 kJ mol-1. Explain the difference in these values.
Date posted: October 4, 2017. Answers (1)
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What is meant by the term 'Enthalpy of formation'?
Date posted: October 4, 2017. Answers (1)
- Element M reacts with water at room temperature to produce 0.2 dm3 of gas. Determine the mass of M which was...(Solved)
Element M reacts with water at room temperature to produce 0.2 dm3 of gas. Determine the mass of M which was reacted with water. (Molar gas volume at room temperature is 24 dm3, Relative atomic mass of M = 7).
Date posted: October 4, 2017. Answers (1)
- A solution was made by dissolving 8.2g of calcium nitrate to give 2 litres of solution. (Ca = 40.0; N = 14.0;...(Solved)
A solution was made by dissolving 8.2g of calcium nitrate to give 2 litres of solution. (Ca = 40.0; N = 14.0; O = 16.0).
Determine the concentration of nitrate ions in moles per litre
Date posted: October 4, 2017. Answers (1)
- When 15cm3 of a gaseous hydrocarbon, P, was burnt in 100cm3 of oxygen, the resulting gaseous mixture occupied 70cm3 at room temperature and pressure....(Solved)
When 15cm^3 of a gaseous hydrocarbon, P, was burnt in 100cm^3 of oxygen, the resulting gaseous mixture occupied 70cm^3 at room temperature and pressure. When the gaseous mixture was passed through potassium hydroxide solution, its volume decreased to 25cm^3.
(a) What volume of oxygen was used during the reaction?
Date posted: October 4, 2017. Answers (1)
- Name one alloy of copper and state its use.
Alloy
Use(Solved)
Name one alloy of copper and state its use.
Alloy
Use
Date posted: October 4, 2017. Answers (1)
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Name two ores from which copper is extracted
Date posted: October 4, 2017. Answers (1)
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A certain mass of gas occupies 146 dm^3 at 291 K and 98.31 kPa. What will be its temperature if its volume is reduced to 133 dm^3 at 101.325 kPa?
Date posted: October 4, 2017. Answers (1)
- A gas jar full gas V was opened in air. Explain the observation made by use of an equation.(Solved)
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Date posted: October 3, 2017. Answers (1)
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paper two.
Date posted: October 2, 2017. Answers (1)
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Date posted: October 2, 2017. Answers (1)
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What is a saturated solution?
Date posted: October 2, 2017. Answers (1)
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Give a reason why nitric (V) acid is stored in dark brown bottles.
Date posted: September 30, 2017. Answers (1)
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State one use of sodium carbonate
Date posted: September 30, 2017. Answers (1)
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What is meant by the term dynamic equilibrium?
Date posted: September 29, 2017. Answers (1)
- a) Name the following processes (i) When anhydrous calcium chloride was left in an open beaker
overnight a solution was formed.(ii) When sodium carbonate decahydrate crystals...(Solved)
a) Name the following processes:
i) When anhydrous calcium chloride was left in an open beaker
overnight a solution was formed.
ii) When sodium carbonate decahydrate crystals are left in an open beaker for some days it turned
into powder.
Date posted: September 29, 2017. Answers (1)