Question regarding Roman Numerals

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Steven Garcia 1H
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Joined: Fri Sep 28, 2018 12:16 am

Question regarding Roman Numerals

Postby Steven Garcia 1H » Fri Oct 05, 2018 1:36 am

I noticed that the answer in the solutions manual for problem L.39 part b shows tin (IV) oxide. I was curious what does the roman numeral IV represent? What's the importance of including it?

Hovik Mike Mkryan 2I
Posts: 95
Joined: Fri Sep 28, 2018 12:25 am

Re: Question regarding Roman Numerals

Postby Hovik Mike Mkryan 2I » Fri Oct 05, 2018 2:02 am

Hello,
Tin is one of the eight elements that can possess more than one type of charge. Tin has two charges, therefore you will see Tin (II) representing Sn2+ and Tin (IV) representing Sn 4+ to specify which charge of tin is in that compound. Hope I helped!

Luc Lorain 1L
Posts: 59
Joined: Fri Sep 28, 2018 12:18 am

Re: Question regarding Roman Numerals

Postby Luc Lorain 1L » Fri Oct 05, 2018 2:25 am

Hello!

The poster above did a great job of explaining the reason for roman numerals being listed beside tin in your problem. This notation is now commonly used for some metals not found within groups 1 and 2 on the periodic table. For these metals, like the previous poster stated, it is possible for some elements to exist in states with various charges assigned to them.

An older notation that might pop up in reading is the "-ic or -ous system", in which instead of using roman numerals after the name of the metal, a particular suffix is attached to modify its name. "-ic" represents the form with greater charge (or greater roman numeral), while "-ous" would be added to the form with the smaller charge or roman numeral.

For example, tin(IV) oxide could be rewritten as stannic oxide (with stan- being roman for tin), whereas tin(II) oxide would be stannous oxide since the tin has a lesser charge (II).

This notation is being phased out for the roman numeral system, but older text might have rely on it!

catzxwang
Posts: 4
Joined: Fri Sep 28, 2018 12:25 am

Re: Question regarding Roman Numerals

Postby catzxwang » Fri Oct 05, 2018 12:32 pm

Luc Lorain 1L wrote:Hello!

The poster above did a great job of explaining the reason for roman numerals being listed beside tin in your problem. This notation is now commonly used for some metals not found within groups 1 and 2 on the periodic table. For these metals, like the previous poster stated, it is possible for some elements to exist in states with various charges assigned to them.

An older notation that might pop up in reading is the "-ic or -ous system", in which instead of using roman numerals after the name of the metal, a particular suffix is attached to modify its name. "-ic" represents the form with greater charge (or greater roman numeral), while "-ous" would be added to the form with the smaller charge or roman numeral.

For example, tin(IV) oxide could be rewritten as stannic oxide (with stan- being roman for tin), whereas tin(II) oxide would be stannous oxide since the tin has a lesser charge (II).

This notation is being phased out for the roman numeral system, but older text might have rely on it!


Couldn't have said it better! The elements with multiple charges that we will likely see most often are the transition metals, found in the middle of the periodic table. One mnemonic to remember the transition metal elements that have different charges (it sounds a bit crazy but works for me!) is Tiny Vicious Creatures are Mean; Females Come at Night to Club, corresponding to Ti V Cr Mn Fe Co Ni Cu.


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