Fact Check: Water boils at 100°C at sea level.

Fact Check: Water boils at 100°C at sea level.

Published July 3, 2025
VERDICT
True

# Fact Check: "Water boils at 100°C at sea level." ## What We Know The claim that "water boils at 100°C at sea level" is a well-established scientifi...

Fact Check: "Water boils at 100°C at sea level."

What We Know

The claim that "water boils at 100°C at sea level" is a well-established scientific fact. Under standard atmospheric pressure at sea level, which is defined as 101.325 kPa (1 atm), water indeed boils at 100°C (or 212°F) (source-2). This boiling point can slightly vary depending on the exact atmospheric pressure, but it is generally accepted as 100°C for practical purposes.

As altitude increases, atmospheric pressure decreases, which in turn lowers the boiling point of water. For example, at an elevation of approximately 1,905 meters (6,250 feet), water boils at about 93.4°C (200.1°F) (source-2). This phenomenon is critical for cooking at high altitudes, where adjustments must be made to cooking times and methods (source-1).

Analysis

The claim is supported by multiple reliable sources, including scientific literature and educational websites. The boiling point of water is a fundamental concept in physics and chemistry, and it is consistently referenced in educational materials. For instance, the Engineering Toolbox explains how the boiling point decreases with altitude due to lower atmospheric pressure, confirming that at sea level, it is indeed 100°C.

Additionally, the NASA source provides a precise definition of the boiling point, noting that it is the temperature at which the vapor pressure of the liquid equals the surrounding pressure. This aligns with the claim that at sea level, water boils at 100°C.

While some sources discuss variations in boiling point due to altitude, they do not contradict the claim; rather, they provide context that reinforces it. For example, the High-altitude cooking article highlights that adjustments are necessary at higher elevations but reiterates the standard boiling point at sea level.

The sources used are credible, with scientific backing and educational intent. They provide a clear understanding of the principles governing boiling points and their dependence on atmospheric pressure.

Conclusion

Verdict: True
The claim that "water boils at 100°C at sea level" is accurate and supported by scientific principles. The boiling point of water is defined under standard atmospheric pressure, and while it changes with altitude, the stated temperature holds true at sea level.

Sources

  1. High-altitude cooking
  2. Boiling point
  3. Boiling Point at Altitude Calculator
  4. Water - Boiling Points vs. Altitude - The Engineering ToolBox
  5. What Temperature Does Water Boil At? Boiling Point & Elevation

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Fact Check: Autistic Non-Verbal Episodes in Marriage: Why Words Vanish Sometimes and What to Do About It Neurodiverse Couples Tuesday, august 12, 2025. Here’s the scene: You’re in the middle of a conversation with your spouse. Maybe the topic is small (“Did you pay the water bill?”) or monumental (“Are we happy?”). And then—without warning—your autistic partner’s voice disappears. No yelling, no slammed doors. Just… gone. You’re left holding the conversational steering wheel while they’ve quietly climbed into the trunk. If you’ve never lived with high-functioning autism, this can be tragically misconstrued as stonewalling or contempt. It isn’t. It’s just neurology pulling the emergency brake. Why This Happens: The Science Without the Lab Coat Smell For autistic adults, losing speech under stress is often a shutdown—a form of nervous system overload that knocks language production offline. Think of it like your phone freezing: all the apps are still there, but none of them open when you tap. Research calls this autistic burnout when it happens in a longer, chronic cycle—linked to masking (Hull et al., 2017; Raymaker et al., 2020). Masking is the art of “performing normal” so well that non-autistic people think you’re fine. The issue is that it eats through your energy reserves like a car idling in traffic with the A/C on full blast (Mantzalas et al., 2022). Eventually, one hard conversation can tip you from functional to frozen. And here’s where couples therapy meets neuroscience: physiological flooding—the body’s fight/flight/freeze switch—is a known relationship killer (Malik et al., 2019; Gottman Institute, 2024). In other words, for some autistic partners, flooding may tend to show up sooner, last longer, and is more likely to pull the plug on speech entirely. The Danger Loop in Marriage Autistic partner goes non-verbal — brain says “nope.” Non-autistic partner reads it as avoidance — brain says “attack.” Pressure increases — “Just say something.” Shutdown deepens — and now you’ve both lost. Do that a few hundred times and you’ll start conflating a physiological response into a moral failing. That’s the real marriage-killer. The Protocol: Three Phases, Zero Guesswork This is where we get practical. You can’t “love away” a temporary shutdown, but you can stop it from turning into World War III. Before: Build the Net Name the state. Agree on a phrase or signal ( I call this a couple code)—such as “words offline,” “shutdown,” a hand over the heart. The point is to make the invisible visible. The Shutdown Card. A literal card that says: I can’t speak right now. Please lower lights, reduce sound, give me X minutes. I promise I will circle back. The Pause Rule. Require a minimum of 20 minutes before resuming any tough talk. Autistic partner may need 90+. Agree ahead of time. Downgrade Kit. the usual gear; earplugs, soft light, weighted blanket, fidget, a quiet room. You know, human decency in object form. Reduce Daily Load. Avoid heavy talks right after work or big social events. Chronic overload makes a nervous shutdown more probable. During: Do Less, Better Autistic Partner: Give the signal. Exit stimulation. Switch channels if possible (text, notes app, yes/no cards). Send a short pre-written message: “Safe, can’t talk, back at 8:15.” Non-Autistic Partner: Acknowledge once—“Got it, I’m with you.” Hold the pause boundary. Lower stimuli. Go regulate your own nervous system—walk, journal, pet the dog. Don’t rehearse comebacks. Both: Avoid sarcasm, interrogation, ultimatums. Nothing lengthens a shutdown like moral outrage. After: Close the Loop Check in: “Are you ready to talk, or should we start in text?” Debrief: Identify triggers and what helped. Solve the actual problem. No conflict gets left to rot in the corner. Spot burnout early. If shutdowns start clustering, it’s time to reduce demands, not double them. How This Isn’t Stonewalling Stonewalling is a choice. Shutdown is a lockout. Stonewalling says, “I won’t talk to you.” Shutdown says, “I can’t talk to you yet, but I will.” The key difference? Repair intention. A shutdown protocol builds that right into the process. The Ten-Minute At-Home Drill Co-create your signal and card. Agree on a pause window. Pack the downgrade kit. Rehearse the exchange (“Got it, I’m with you.”). Check in weekly to tweak the system. Remember, you’re not aiming for zero shutdowns. You’re aiming for shorter, kinder, safer ones. Why This Works Because it matches lived autistic experience (Raymaker et al., 2020; Lewis et al., 2023). Because it honors nervous system limits instead of punishing them (Malik et al., 2019). Because it lets both partners keep their dignity and still solve the problem. In other words: you’re building a marriage that can survive the occasional moments when the words are gone for the time being. Be Well, Stay Kind, and Godspeed. REFERENCES: Hull, L., Mandy, W., Lai, M.-C., Baron-Cohen, S., Allison, C., Smith, P., & Petrides, K. V. (2017). “Putting on my best normal”: Social camouflaging in adults with autism spectrum conditions. Autism, 21(5), 611–622. https://doi.org/10.1177/1362361316671012 Raymaker, D. M., Teo, A. R., Steckler, N. A., Lentz, B., Scharer, M., Delos Santos, A., … & Nicolaidis, C. (2020). “Having all of your internal resources exhausted beyond measure and being left with no clean-up crew”: Defining autistic burnout. Autism in Adulthood, 2(2), 132–143. https://doi.org/10.1089/aut.2019.0079 Mantzalas, J., Richdale, A. L., Adikari, A., Lowe, J., & Dissanayake, C. (2022). What Is Autistic Burnout? A thematic analysis of posts on two online platforms. Autism in Adulthood, 4(1), 52–65. https://doi.org/10.1089/aut.2021.0079 Lewis, L. F., et al. (2023). The lived experience of meltdowns for autistic adults. Autism, 27(7), 1787–1799. https://doi.org/10.1177/13623613221145783 Malik, J., et al. (2019). Emotional flooding in response to negative affect in romantic relationships. Journal of Couple & Relationship Therapy, 18(4), 327–349. https://doi.org/10.1080/15332691.2019.1641188 Gottman Institute. (2024, March 4). Making sure emotional flooding doesn’t capsize your relationship. Retrieved from https://www.gottman.com/blog/making-sure-emotional-flooding-doesnt-capsize-your-relationship/

Detailed fact-check analysis of: Autistic Non-Verbal Episodes in Marriage: Why Words Vanish Sometimes and What to Do About It Neurodiverse Couples Tuesday, august 12, 2025. Here’s the scene: You’re in the middle of a conversation with your spouse. Maybe the topic is small (“Did you pay the water bill?”) or monumental (“Are we happy?”). And then—without warning—your autistic partner’s voice disappears. No yelling, no slammed doors. Just… gone. You’re left holding the conversational steering wheel while they’ve quietly climbed into the trunk. If you’ve never lived with high-functioning autism, this can be tragically misconstrued as stonewalling or contempt. It isn’t. It’s just neurology pulling the emergency brake. Why This Happens: The Science Without the Lab Coat Smell For autistic adults, losing speech under stress is often a shutdown—a form of nervous system overload that knocks language production offline. Think of it like your phone freezing: all the apps are still there, but none of them open when you tap. Research calls this autistic burnout when it happens in a longer, chronic cycle—linked to masking (Hull et al., 2017; Raymaker et al., 2020). Masking is the art of “performing normal” so well that non-autistic people think you’re fine. The issue is that it eats through your energy reserves like a car idling in traffic with the A/C on full blast (Mantzalas et al., 2022). Eventually, one hard conversation can tip you from functional to frozen. And here’s where couples therapy meets neuroscience: physiological flooding—the body’s fight/flight/freeze switch—is a known relationship killer (Malik et al., 2019; Gottman Institute, 2024). In other words, for some autistic partners, flooding may tend to show up sooner, last longer, and is more likely to pull the plug on speech entirely. The Danger Loop in Marriage Autistic partner goes non-verbal — brain says “nope.” Non-autistic partner reads it as avoidance — brain says “attack.” Pressure increases — “Just say something.” Shutdown deepens — and now you’ve both lost. Do that a few hundred times and you’ll start conflating a physiological response into a moral failing. That’s the real marriage-killer. The Protocol: Three Phases, Zero Guesswork This is where we get practical. You can’t “love away” a temporary shutdown, but you can stop it from turning into World War III. Before: Build the Net Name the state. Agree on a phrase or signal ( I call this a couple code)—such as “words offline,” “shutdown,” a hand over the heart. The point is to make the invisible visible. The Shutdown Card. A literal card that says: I can’t speak right now. Please lower lights, reduce sound, give me X minutes. I promise I will circle back. The Pause Rule. Require a minimum of 20 minutes before resuming any tough talk. Autistic partner may need 90+. Agree ahead of time. Downgrade Kit. the usual gear; earplugs, soft light, weighted blanket, fidget, a quiet room. You know, human decency in object form. Reduce Daily Load. Avoid heavy talks right after work or big social events. Chronic overload makes a nervous shutdown more probable. During: Do Less, Better Autistic Partner: Give the signal. Exit stimulation. Switch channels if possible (text, notes app, yes/no cards). Send a short pre-written message: “Safe, can’t talk, back at 8:15.” Non-Autistic Partner: Acknowledge once—“Got it, I’m with you.” Hold the pause boundary. Lower stimuli. Go regulate your own nervous system—walk, journal, pet the dog. Don’t rehearse comebacks. Both: Avoid sarcasm, interrogation, ultimatums. Nothing lengthens a shutdown like moral outrage. After: Close the Loop Check in: “Are you ready to talk, or should we start in text?” Debrief: Identify triggers and what helped. Solve the actual problem. No conflict gets left to rot in the corner. Spot burnout early. If shutdowns start clustering, it’s time to reduce demands, not double them. How This Isn’t Stonewalling Stonewalling is a choice. Shutdown is a lockout. Stonewalling says, “I won’t talk to you.” Shutdown says, “I can’t talk to you yet, but I will.” The key difference? Repair intention. A shutdown protocol builds that right into the process. The Ten-Minute At-Home Drill Co-create your signal and card. Agree on a pause window. Pack the downgrade kit. Rehearse the exchange (“Got it, I’m with you.”). Check in weekly to tweak the system. Remember, you’re not aiming for zero shutdowns. You’re aiming for shorter, kinder, safer ones. Why This Works Because it matches lived autistic experience (Raymaker et al., 2020; Lewis et al., 2023). Because it honors nervous system limits instead of punishing them (Malik et al., 2019). Because it lets both partners keep their dignity and still solve the problem. In other words: you’re building a marriage that can survive the occasional moments when the words are gone for the time being. Be Well, Stay Kind, and Godspeed. REFERENCES: Hull, L., Mandy, W., Lai, M.-C., Baron-Cohen, S., Allison, C., Smith, P., & Petrides, K. V. (2017). “Putting on my best normal”: Social camouflaging in adults with autism spectrum conditions. Autism, 21(5), 611–622. https://doi.org/10.1177/1362361316671012 Raymaker, D. M., Teo, A. R., Steckler, N. A., Lentz, B., Scharer, M., Delos Santos, A., … & Nicolaidis, C. (2020). “Having all of your internal resources exhausted beyond measure and being left with no clean-up crew”: Defining autistic burnout. Autism in Adulthood, 2(2), 132–143. https://doi.org/10.1089/aut.2019.0079 Mantzalas, J., Richdale, A. L., Adikari, A., Lowe, J., & Dissanayake, C. (2022). What Is Autistic Burnout? A thematic analysis of posts on two online platforms. Autism in Adulthood, 4(1), 52–65. https://doi.org/10.1089/aut.2021.0079 Lewis, L. F., et al. (2023). The lived experience of meltdowns for autistic adults. Autism, 27(7), 1787–1799. https://doi.org/10.1177/13623613221145783 Malik, J., et al. (2019). Emotional flooding in response to negative affect in romantic relationships. Journal of Couple & Relationship Therapy, 18(4), 327–349. https://doi.org/10.1080/15332691.2019.1641188 Gottman Institute. (2024, March 4). Making sure emotional flooding doesn’t capsize your relationship. Retrieved from https://www.gottman.com/blog/making-sure-emotional-flooding-doesnt-capsize-your-relationship/

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Fact Check: Water boils at 100°C at sea level. | TruthOrFake Blog