Why is this statement false and not true?

The elements calcium, cobalt, copper, cadmium are listed in order from smallest to largest in atomic size. Can anyone explain to me? Thanks!Why is this statement false and not true?
According to the periodic table, it isn't false.Why is this statement false and not true?
Guess no one got a chance to vote on this and the asker wasn't in the mood to choose.





False because of size....see several answers below

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Well, when they say smallest to largest, I am assuming that they are talking about atomic radius. The rdius gets bigger as more electrons are present.
look in ur periodic table.
I'm sorry I don't have that much time in my hands, but I know this will help you a lot. Please look at the link. ;)


Good luck!!1


~J
If you go here it gives you the sizes of each it is measured by weight.


http://periodic.lanl.gov/default.htm


Name: Calcium


Symbol: Ca


Atomic Number: 20


Atomic Mass: 40.078 amu


Melting Point: 839.0 掳C (1112.15 K, 1542.2 掳F)


Boiling Point: 1484.0 掳C (1757.15 K, 2703.2 掳F)


Number of Protons/Electrons: 20


Number of Neutrons: 20


Classification: Alkaline Earth


Crystal Structure: Cubic


Density @ 293 K: 1.55 g/cm3


Color: Silvery





Name: Cobalt


Symbol: Co


Atomic Number: 27


Atomic Mass: 58.9332 amu


Melting Point: 1495.0 掳C (1768.15 K, 2723.0 掳F)


Boiling Point: 2870.0 掳C (3143.15 K, 5198.0 掳F)


Number of Protons/Electrons: 27


Number of Neutrons: 32


Classification: Transition Metal


Crystal Structure: Hexagonal


Density @ 293 K: 8.9 g/cm3


Color: silver





Name: Copper


Symbol: Cu


Atomic Number: 29


Atomic Mass: 63.546 amu


Melting Point: 1083.0 掳C (1356.15 K, 1981.4 掳F)


Boiling Point: 2567.0 掳C (2840.15 K, 4652.6 掳F)


Number of Protons/Electrons: 29


Number of Neutrons: 35


Classification: Transition Metal


Crystal Structure: Cubic


Density @ 293 K: 8.96 g/cm3


Color: red/orange





Name: Cadmium


Symbol: Cd


Atomic Number: 48


Atomic Mass: 112.411 amu


Melting Point: 320.9 掳C (594.05 K, 609.62 掳F)


Boiling Point: 765.0 掳C (1038.15 K, 1409.0 掳F)


Number of Protons/Electrons: 48


Number of Neutrons: 64


Classification: Transition Metal


Crystal Structure: Hexagonal


Density @ 293 K: 8.65 g/cm3


Color: Silvery
Check the Periodic Table.





The atomic weight for each is usually listed below the element's symbol.





Ca = 40.08


Co = 58.93


Cu = 63.55


Cd = 112.4





So it isn't false, it's true by weight.





But what about atomic radius? That would be 'size' but in a different way....





In the periodic table, atomic radii increase down a group as new electron shells are added, and decrease left-to-right as the nuclear charge (or number of protons) is increased.





So, as ca, co, cu, and cd are on the Periodic Table, the radius decreases in that order.





Maybe that's it?
Try looking in your chemistry book where they have the periodic table. (or find the periodic table online)
By ';atomic size'; are you assuming atomic number?





If you look at the atomic radii of these, they are not in order from smallest to largest. It would be Copper (Cu), Cobalt (Co), Cadmium (Cd), Calcium (Ca)
False is the same as not true but you still need to do your own homework...sorry.