Question

17 and 18 questions no.

Answer 1

HELLO THERE!

Some metal compounds impart colour to flames, these are questions on that.

First, we should know some common salts that impart colour to flames:

=> Sodium (Na): Golden Yellow

=> Potassium (K): Purple (lilac)

=> Copper (Cu): Peacock Bluish green

=> Barium (Ba): Green

Now, go to your question:

Q17. A + O₂ ----> B

B gives golden yellow colour, so it must be an oxide of Sodium.

So, A = Sodium (Na) and B = Sodium oxide (Na₂O).

Reaction: 4Na + O₂ ----> 2Na₂O

Q18. C + O₂ ----> D

D imparts bluish green colour, so D must be oxide of copper.

So, C = Copper (Cu) and D = Copper oxide (CuO).

Reaction: 2Cu + O₂ ----> 2CuO

HOPE MY ANSWER IS SATISFACTORY...

Thanks!