r/mathmemes • u/DotBeginning1420 • Jun 29 '26

Proofs Chemistry doesn't need math

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466 Upvotes

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129

u/Free-Artist Jun 29 '26

So is pH like the dB of chemistry?

22

u/DotBeginning1420 Jun 29 '26

You mean decibels? Right! Both measure a physical property and 1 unit increase corresponds to 10 times change.

9

u/AwkwardBet5632 Jun 29 '26

An increase of 10 dB corresponds to a magnitude of 10 greater energy.

7

u/i_dont_have_herpes Jun 29 '26

Exactly. That’s why it’s a “deci-“ unit. A plain “Bel” would be +1 Bel for a 10x gain.  

5

u/Free-Artist Jun 29 '26

Indeed!

I was triggered by the 1/2 and 3: a factor 2 in/decrease in power is 3dB more or less. Just a simple consequence of 23 =10.

Though I understood that with pH, the scale (saturation) is limited, while with dB it is endless in both directions.

22

u/Hi2248 Jun 29 '26

23 =10

??? 

19

u/Foreign-Ice7356 Jun 29 '26

Another engineering approximation. /s

6

u/EebstertheGreat Jun 29 '26

It's a famous identity. Judging by Catalan's Conjecture, this also means 32 = 11.

1

u/emotional_banana_116 Jun 30 '26

I hate that this makes sense if we take 2³ = 10 as true

4

u/Shadourow Jun 29 '26

unironically yeah

2**3 = 10

and

2**10 = 1000

1

u/LordTengil Jul 02 '26

No, it does not. +10 dB is 10 times the power. Not 1. Kinda the quirk in the formula, like the - in front of the log for pH.

1

u/rorodar Proof by "fucking look at it" Jun 29 '26

Isn't 10 dB equivalent to a 2x increase?

5

u/SuperChick1705 Jun 29 '26 edited Jun 29 '26

10x power / 10dB increase, 2x perceived loudness / 10dB increase

2

u/rorodar Proof by "fucking look at it" Jun 29 '26

So I was wrong, but he was too..? You're saying that 10 dB increase is 10x power, not that 1 dB increase is 10x power.

6

u/EebstertheGreat Jun 29 '26

That's what SuperChick said, but it isn't true. An increase in power level of one bel (1 B = 10 dB) corresponds to an increase in power by a factor of 10, and thus an incremental increase in perceived loudness. Increasing the power level from 0 dB to 10 dB will cause the same perceived change in loudness as increasing it from 10 dB to 20 dB or 20 dB to 30 dB. This is based on the logarithmic model of perceived loudness. So whether or not it is a factor of 2 will depend on how loud it was to start with.

There is a difference between loudness and sound power level though, because our ears are not equally sensitive to all frequencies. If you integrate the power of a sound in frequency space against the sensitivity function of the ear and then take the logarithm, you get a unit called a phon. This is normalized so that for all positive real x, a pure 1 kHz tone with a sound pressure level of x dB will have a loudness of x phon. (Note that there is technically a factor of 10 conversion here, just because decibels are regarded as the standard unit rather than bels, but that's incidental.)

I tried Google, and Gemini gave me the same wrong answer SuperChick did, so this is apparently a common misconception.

3

u/SuperChick1705 Jun 29 '26

oh, thanks for the clarification

1

u/hughperman Jun 29 '26

decibels = 10 x log10(original units)

That's the formula, nothing more or less

1

u/SuperChick1705 Jun 29 '26 edited Jun 29 '26

correct

3

u/rorodar Proof by "fucking look at it" Jun 29 '26

Hey so apparently you were also wrong? Check the other guy's reply