Which statement is not true about the elements flourine, chlorine, and iodine?
a) they are all halogens
b) they react easily with metals
c) they are similar to noble gases
d) they are all nonmetals

The fluorine, iodine, and chlorine are c) They are similar to noble gases.

Nobel gas refers to those substances which doesn't have any vacant shell. They are completely filled. They are electron haters and are really hard to make them involve in chemical reaction. On the other hand, gases such as chlorine, bromine and iodine are called as halogens. They have ability to accommodate one electron in their valence shell as they have 7 already.

Thus, it can be inferred that gases such as chlorine, bromine and iodine are not similar to Nobel gas and thus the statement C which states they are similar to Nobel gas is considered as false.

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3