You can answer this question by only searching the element in the periodic table.
The atomic number of iodine, I, is 53. It is placed in the column 17 (this is the Group) and row 5 (this is the Period).
The conclusion is that the iodine is located in Period 5, Group 17, and is classified as a nonmetal.
❌formed by 2 ions
❌ionic bonds
✅yes because of solvation
✅yes electrolytes are substances that break apart into ions when dissolved
✅in itself but salt water is a good conductor
✅such as water
2HNO3 + Ca(OH)2 --> 2HOH + Ca(NO3)2
Answer : The correct option is, (B) 
Solution :
According to the Graham's law, the rate of effusion of gas is inversely proportional to the square root of the molar mass of gas.
or,
..........(1)
where,
= rate of effusion of unknown gas = 
= rate of effusion of oxygen gas = 
= molar mass of unknown gas = ?
= molar mass of oxygen gas = 32 g/mole
Now put all the given values in the above formula 1, we get:
The unknown gas could be carbon dioxide 
that has approximately 44 g/mole of molar mass.
Thus, the unknown gas could be carbon dioxide
