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A : When borax is strongly heated it for...

A : When borax is strongly heated it forms transparent glassy bead .
R : Borax is the other name for sodium tetraborate decahydrate.

A

Both Assertion & Reason are true and the reason is the correct explanation of the assertion

B

Both Assertion & Reason are true but the reason is not the correct explanation of the assertion

C

Assertion is true statement but Reason is false

D

Both Assertion and Reason are false statements

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the two statements provided: **Assertion (A):** When borax is strongly heated, it forms a transparent glassy bead. **Reason (R):** Borax is the other name for sodium tetraborate decahydrate. ### Step-by-Step Solution: 1. **Understanding Borax:** - Borax is a compound with the chemical formula Na₂B₄O₇·10H₂O, which is known as sodium tetraborate decahydrate. The term "decahydrate" indicates that there are 10 water molecules associated with each formula unit of borax. 2. **Heating Borax:** - When borax is strongly heated, it undergoes a process where it first loses its water molecules. The reaction can be represented as: \[ \text{Na}_2\text{B}_4\text{O}_7 \cdot 10\text{H}_2\text{O} \rightarrow \text{Na}_2\text{B}_4\text{O}_7 + 10\text{H}_2\text{O} \] - After losing water, the remaining sodium tetraborate (Na₂B₄O₇) can further decompose upon heating to form sodium metaborate (NaBO₂) and boric anhydride (B₂O₃). 3. **Formation of Glassy Beads:** - The sodium metaborate and boric anhydride can combine to form a transparent glassy bead upon cooling. This is a characteristic property of borax when heated strongly. 4. **Evaluating the Assertion:** - The assertion states that heating borax results in a transparent glassy bead, which is true based on the chemical reactions described. 5. **Evaluating the Reason:** - The reason states that borax is another name for sodium tetraborate decahydrate, which is also true. 6. **Conclusion:** - Both the assertion and the reason are true. However, the reason does not directly explain why the assertion is true; it simply states what borax is. Therefore, the correct conclusion is that both statements are true, but the reason is not the correct explanation for the assertion. ### Final Answer: Both assertion and reason are true, but the reason is not the correct explanation for the assertion.
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Borax Bead Test is carried out when the original mixture is coloured. It is done with the help of a cleam platinum wire on which a small loop is made at the end. When borax is heated on platinum wire loop transparent glass like bead is obtained. The hot bead is brought in contact with salt till it reacts with fused borax and colour is imparted to the bead. bead colour is noted. {:("Colour of the bead","Ion"),(1." Blue green",Cu^(2+)),(2." Yellow ",Fe^(3+)),(3." Green",Cr^(3+)),(4." Violet",Mn^(2+)),(5." Dark blue",Co^(2+)),(6." Brown",Ni^(2+)):} Q. The flame used in Borax Bead Test is:

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