Question

In thermite welding, to ignite the mixture we use:
A. Magnesium ribbon
B. Potassium ribbon
C. Calcium ribbon
D. Manganese ribbon

Answer 1

Hint: Thermite is a mixture of the metal powder and metal oxide. Thermite undergoes exothermic reaction when ignited. The exothermic reaction is a redox reaction in which both oxidation and reduction reactions occur.

Complete Solution :
 - In the question it is given what chemical we use in thermal welding.
- Generally in thermite welding a huge amount of heat is required.
- In thermite welding aluminum powder and metal oxide has to be heated at high temperature to make the exothermic redox reaction.
- The booster material used to maintain such a huge temperature for exothermic redox reaction is magnesium ribbon.
- Therefore In thermite welding, to ignite the mixture we use Magnesium ribbon.
So, the correct answer is “Option A”.

Additional information-
- If we use aluminium in the thermite reaction then it is called the Goldsmith alumino thermic reaction.
- To trigger the goldsmith alumino thermic reaction the magnesium ribbon has to be burned in the presence of barium peroxide.
- In thermite reaction metal oxide is converted to metal at high temperature.

Note: The composition of the Iron thermite is $F{{e}_{2}}{{O}_{3}}$ and aluminium, the composition of the chromium thermite is $C{{r}_{2}}{{O}_{3}}$ and aluminum, and the composition of copper thermite are CuO and Aluminium. A common thermite contains 3:1 ratio of ferric oxide and aluminium by mass used for welding of the iron broken parts.