Write the formulas of alkanes that contain 3,5,7 and 9 carbon atoms

Explanation:

You're referring to propane,pentane, heptane and nonane.

The formula for alkanes is CnH2n+2

For propane C3H8

Pentane C5H12

Heptane C7H16

Nonane C9H20

colorless gas, exhibiting a blue glow when placed in an electric field

b) solid

its a type of rock

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.