Anomalous Behaviour of Oxygen

Q.

Explain Group $\mathrm{VIII}$ Elements.

Q.

What are the four big elements of the living body?

Q.

The position of certain elements in the Modem Periodic Table is shown below. Using the above table answer the following questions giving reasons in each case: Which element will form only covalent compounds?

B BYJUS

Q. calculate the number of oxygen atoms in 1 litr air if air contains 20% O_2.

Q. Colour of liquid oxygen is

1. colourless
2. pale yellow
3. pale blue

Q. A soft metal $\left(A\right)$ gives violet flame test. When burnt ill excess $O_2$ , $\left(A\right)$ gives chrome yellow powder $\left(B\right)$ which on reaction with water gives alkaline solution $\left(C\right)$ and $O_2$. Identify $A$ and $B$.

1. $Na,N{a}_2{O}_2$
2. $K,K{O}_2$
3. $K,K_2{O}_{2}Z$
4. $Li,L{i}_2{O}_2$