Tuesday 29 March 2016

2.19 describe the reactions of magnesium, carbon and sulphur with oxygen in air, and the acid-base character of the oxides

When anything is burnt, it reacts with oxygen in the air to form oxides (which can have wither acidic or basic character). 

Magnesium
When magnesium burns in air, it produces a bright white flame and a white powder is formed (this is magnesium oxide). Magnesium oxide is slightly alkali when dissolved in water.

The equation for the reaction (burning Mg in air) is 2Mg(s) + O2(g) ---> 2MgO(s)

NOTE: This question often comes up in exams so make sure you know it!

Carbon
Carbon will only burn in air if it is very strongly heated. It burns with a yellowy-orangey flame and produces carbon dioxide (as a gas). Carbon dioxide is slightly acidic when dissolved in water.

The equation for the reaction (burning C in air) is C(s) + O2(g) ---> CO2(g)

Sulfur
Sulphur burns (in air) with a pale blue flame and produces sulfur dioxide which is acidic when dissolved in water.

The equation for this reaction (burning S in air) is C(s) + O2(g) ---> SO2(g)

1 comment:

  1. Lyso-gangliosides are prepared by removing glycolipid enzymatically from natural gangliosides. They can be used to analyze various cell function, such as cell proliferation, differentiation, apoptosis, signal transduction, etc. It can also be used as a material of ganglioside derivatives in RI labeling, fluorescence labeling, immobilization since they have free amino group in sphingosine. Native Lyso-GM2 Enzyme

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