Question about Texas Instruments TI-30XA Calculator

# Hydrogen ions to ph

How do I covert H+ ions(2.9*10^-4) to ph? I need the keys used specifically.

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• koji83732984 Mar 17, 2009

And what about the reverse project. Which key on the calculator gives anti-log?!

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It should be this sequence:
2.9 {EE} 4 {+ -> -} will give you the Sci.Not.
Then {=} (0.00029)
Then {LOG} (-3.537602002)
Then {+ -> -} (3.537602002)
pH=3.54

Posted on Mar 05, 2009

Hi,
a 6ya Technician can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
Goodluck!

Posted on Jan 02, 2017

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## Related Questions:

### What does pH stand for?

the p stands for potential and the H stands for Hydrogen, and it refers to the ability to attract hydrogen ions.

Jan 28, 2013 | Measuring Tools & Sensors

Tip

### Using a pH meter to care for your fish

pH values are the acidity of a body of water. Neutral water has a value of 7.0 meaning that it has equal amounts of hydrogen ions and hydroxide ions. When more hydrogen ions are added the water then the number goes down and the water becomes more acidic, or if the amount of hydroxide ions goes up then the water becomes more alkaline.

pH levels in your fish tank can prove to be fatal if they aren't monitored properly. While there is no secret formula for the perfect pH level for all fish it is best to keep all the fish from the same bodies of water together. Salt water fish shouldn't be put in a tank with freshwater fish because they need different pH levels.

Throughout the day the pH level of your fish tank will change although these slight changes shouldn't be too harmful on your fish sudden changes will prove to be fatal. When you are moving fish from one tank to another you want to make sure that the two waters have the same pH levels. When you want to buy a new fish check the pH level of your fish tank and then the pH level of the water at the pet shop to make sure that the levels are not too different.

You should be checking the pH levels of your fish tank at least once a month, but more often is always better. When you take the pH level you should write it down in a log book. You should try to take the pH level at the same time every time you take a reading because at different times of the day the levels would be different. Try to keep yourself from going crazy, if the pH level is a few decimals off of perfect your fish will be okay. If the level is fairly regular you shouldn't have to do anything unless your fish show signs of distress.

on Feb 02, 2014 | Measuring Tools & Sensors

### Explain the relationship between pH and relative concentration of hydrogen and hydroxide ions in a solution

The pH scale is a logarithmic scale used to measure the concentrations of hydrogen/Hydronium ions in an aqueous solution.
If c[H] is the concentration of hydrogen ions in mol/L, the pH is defined as
pH=-log(c[H]).
Inversely, the concentration is given by
c[H]=10^(-pH)
The pOH=14-pH

Jan 19, 2012 | Office Equipment & Supplies

### TI-30XIIs How to calculate pH

pH is defined as the negative logarithm of the hydrogen ion activity in a solution:

The value is defined as the molar concentration of H+ Ions, multiplied by a correction factor, the activity coefficient. The activity coefficient is required because in nature there are rarely actual H+ ions in a solution. For example, in water H+ ions combine with water molecules to Oxonium and Hydronium ions:

The associated products are less reactive than H+ ions would be, so the activity coefficient is always greater than 0 and smaller than 1. It depends on plenty of factors, e.g. the temperature of the solution, or the presence of other substances, and is very difficult to determine precisely.

For this reason, in water solutions the pH is usually approximated by:

for other solutions (not in water), similar approaches exist, but the resulting "pH" equivalents are not directly comparable.

Long story short: get the H3O+ concentration in mol/L by measuring it, or from the problem text. For example, if the concentration is 0.003 mol/L, key in:

and get a pH of 2.52

Feb 02, 2011 | Texas Instruments TI-30XA Calculator

### Ph level for saltwater intex system is too high and water is a bit cloudy what do I do?

Get your water tested at your local pool store and they are going to tell you to add Muriatic Acid. Follow their instructions carefully, hopefully they are a good company. Salt water systems tend to drift the pH slightly basic (high) because of the offgasing of Hydrogen ions in the water. Hayward Mineral Springs salt has pH and alkalinity buffers in the salt already, depending on what brand of salt you are using, that might be your problem.

Jul 07, 2010 | Intex Automatic Salt Water System for ...

### How do i enter pH on a TI 30 calculator

Hello,
1. How to obtain the concentration knowing the pH?
2. How to obtain the pH knowing the concentration
If you are not interested in the theory, jump to the examples at the end of the post.

As you well know the pH is the negative of the log in base 10 of the H+/H3O+ ion concentration. If we use [H+] to represent that concentration, then pH=-log[H+].
To obtain the [H+] you need to calculate the antilog. You write the definition in the form log[H+] =-pH and then calculate 10 to the power of each member. The equality remains valid as both members are treated similarly. Thus
10^( log[H+] ) = 10^(-pH)
Since raising 10 to a power is the inverse function of taking the log in base 10, 10^(log(x))=log(10^(x)) = x (they are inverse of one another), you are left with

[H+]=10^(-pH)

Your calculator has a function [10 to x] accessed by pressing the [2nd] function key. To use it you must enter the negative value of the pH, press the [2nd] function key then the [10 to x], then the = key to get the result (concentration)
Examples

1. Let the pH=5.5, what is the H+ concentration?

With [(-)] being the change sign key, then
[H+]:[ (-) ] 5.5 [2nd][10 to x] [=]
The result is 0.000003162 or 3.16 x 10^(-6)

Calculating the pH

Shortcut:
For all H+/H3O+ concentrations of the form 1.*10^(a) where a is an integer number between 0 and -14, the pH is the negative value of the exponent.
Concentration =10^(-3), pH=3
Concentration=10^(-11), pH=11

For other concentrations such as 3.567*10^(-8), one cannot use the shortcut above, but have to calculate the log of the concentration

[H+/H3O+] = 3.567*10^(-8)
pH= - log(3.567*10^(-8))
This is keyed in as follows (to minimize the number of parentheses)

8 (-) [2nd][10 to x] [*] 3.567 [LOG] [=] (-)
Here you have two (-) change sign, the first is entered after the exponent of 10, the other at the end of the calculation to take the negative of the displayed result. You may notice that it is entered in the reverse order of the defining relation - log(3.567*10^(-8)).
To verify your calculation, the result is 7.447696891 or just 7.45
If you have a problem with the first (-) try entering it before you type in 8.

Hope it helps and thank you for using FixYa

Dec 07, 2009 | Texas Instruments TI-30XA Calculator

### How to use antilog?

Hello,

As you well know the pH is the negative of the log in base 10 of the H+/H3O+ ion concentration. If we use [H+] to represent that concentration, then pH=-log[H+].
To obtain the [H+] you need to calculate the antilog. You write the definition in the form log[H+] =-pH and then calculate 10 to the power of each member. The equality remains valid as both members are treated similarly. Thus
10^( log[H+] ) = 10^(-pH)
Since raising 10 to a power is the inverse function of taking the log in base 10, 10^(log(x))=log(10^(x)) = x (they are inverse of one another), you are left with

[H+]=10^(-pH)

Your calculator has a function [10 to x] accessed by pressing the [2nd] function key. To use it you must enter the negative value of the pH, press the [2nd] function key then the [10 to x], then the = key to get the result (concentration)
Exemple: let the pH=5.5, what is the H+ concentration?
With [(-)] being the change sign key, then
[H+]:[ (-) ] 5.5 [2nd][10 to x] [=]
The result is 0.000003162 or 3.16 x 10^(-6)

Hope it helps.

Dec 07, 2009 | Texas Instruments TI-30XA Calculator

### Cannot figure out how to use the reverse log on my Staples Textbook display BD-6410 Calculator the pOH is 6.59 I need to use the reverse log to get the answer for the H+ which is the reverse log of 6.59...

Hello,

You should use the equivalence
y=10^(x) is equivalent to x=log(y)

You should not use word that have no meaning. x above is sometimes called antilog, not reverse log.

The relation linkin pH and pOH is as follows
pH+pOH=14, thus pH=14-pOH

Let c[H+] be the concentation (or if you use the hydronium ion, instead of H+ ) c[H3O+] the concentration of hydronium ion)
c[H+]=c[H3O+]=10^(-pH)

pOH= 6.95 thus pH=14-6.95 = 7.05
If pH=7.05 the c[H+]= 10 ^(-7.05) =8.9125E(-8)

pH= 10^ [X to the power] [(-)]7.05
The key/buttom to raise to the power is the one to the right of x squared

Hope it helps

Sep 10, 2009 | Texas Instruments Office Equipment &...

pH is minus (log to base 10) of the hydrogen ion activity of an aqueous solution, or (log to base 10) of (1/hydrogen ion activity)

To get the inverse log, i.e the hydrogen ion activity corresponding to a specified pH, simply enter the pH value and press

2nd
LOG
1/x

Apr 22, 2008 | Texas Instruments TI-30XA Calculator

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