[philonossis]

I could not figure out the best forum to post this question on.

I am trying to get the most reliable calculator that can be used at undergrad level chemistry.  That would mean 8 to 12 figures.

I bought a casio with a "solar battery" on the top front. I do all my work inside at night, however, so it is rarely in the sun.

It appears to have given out after about 4 months, and the store offers no guaranty.

Some calculators may take a battery that can be replaced, others do not.

I would prefer not having to spend $10+ dollars every 4 months getting a new calculator.

There are other models of Casio, as well as Citizen, etc.

I am not looking for anything advanced or that uses Programs, just a keyboard calc that won't give out.

Can anyone suggest a solution?

[Borek]

Number of figures is not that important, 8 is more than you will ever need. What you need is a scientific notation (6.02x10²³) and functions like log & exp (trigonometric won't hurt as well).

If it failed after 4 months it is either bad luck or lack of care, I have several calculators somewhere here, some over 10 years old, all working.

[AWK]

My Casio FX-250E works over 25 years.

My advice - completely free online calculator with periodic table in memory:
http://www.creative-chemistry.org.uk/alevel/calculator.htm

[philonossis]

Borek and AWK:
Thanks for these responses.

I am wondering if it is better to get a solar battery calc. which is the one that just went bad on me, or one with batteries that can be replaced.

Some calculators have a removable back for repair.  These might be salvageable.

[gluedudeguru]

I don't know what you mean by "chemistry calculator" but my TI-85 got me through 3 years of HS (Calculus and the like) 5 years of college calc and got me a BS in chemistry.  I would trust the thing with my life.  Sometimes if i ask nicely it makes me sandwiches, but i got the special model .  TI-86 is the way to go (most TI above this are prohibited in classrooms because of their computing power)

[DemonicAcid]

I've used a TI-89 for the past 7 years. Since all of my math classes have been purely proof based it wasn't a problem, however most teachers did ban that particular calculator. I would recommend the highest level TI that your classes allow you to use.