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Part 2 · Episode 24 B1-B2

If You Heat Water…

📐 Zero Conditional (general truths)

Michael Faraday · 1831: Faraday's electromagnetic demonstration 📖 5 min read

Episode 24: If You Heat Water…

Zero Conditional — Michael Faraday, 1831 (B1-B2)

Grammar Box

Meaning: Zero conditional describes scientific facts, general truths, and things that always happen under certain conditions.

Form: If + present simple, present simple. (Both clauses use present tense; order can reverse: “Water boils if you heat it to 100°C.”)

Example 1: “If you mix red and blue, you get purple.” (Always true, scientific fact.)

Example 2: “If I don’t sleep enough, I feel terrible.” (Personal routine/habit that’s always true for me.)

Common mistake: Wrong: “If you heat water, it will boil.” Better: “If you heat water, it boils.” (Zero conditional uses present, not ‘will.’)

The Challenge

Luna read a science article: “If you heat water to 100°C, it will boil.” Professor Wisdom circled ‘will.’ “That’s first conditional—prediction. But for scientific facts, we use zero conditional: simple present in both parts.” Luna tried: “If you heat water to 100°C, it boils?” “Exactly,” he nodded. “No ‘will,’ because it’s not a prediction. It’s a law of nature.” The watch glowed. “Let’s see someone who taught the world through simple truths.”

The Journey

London, 1831. The Royal Institution’s lecture hall buzzed with curious minds as Michael Faraday, a self-taught scientist in his forties, prepared his demonstration. Born poor, without formal university education, Faraday had worked his way from bookbinder’s apprentice to one of Britain’s greatest experimental physicists through pure curiosity and relentless observation.

Today he would reveal electromagnetic induction, the principle behind modern electricity. But Faraday never presented his discoveries as complex mysteries. He believed science belonged to everyone, explained through cause and effect anyone could understand.

He held up a coil of wire and a magnet. “Watch carefully,” he said, his voice calm and clear. “If I move this magnet through the coil, a current flows in the wire.” He demonstrated. A needle flickered on a meter. “Every time. Not sometimes. Always. If you move a magnet through a conductor, you generate electricity. If you stop moving it, the current stops.”

The audience leaned forward. Some were scientists; others, factory owners, teachers, curious citizens. Faraday smiled. “This isn’t magic or theory. If you repeat my actions, you get the same result. Science doesn’t depend on who you are or what you believe. If the conditions are right, nature responds. Always.”

That simple principle—stated in present tense, describing permanent truth—would power the industrial revolution.

The Deep Dive

Zero conditional expresses facts that are always true when certain conditions exist. We use present simple in both clauses because we’re describing reality, not speculation. This differs from first conditional (if + present, will + base verb) which makes predictions about specific future events.

Compare: “If you heat ice, it melts” (zero—always true) vs. “If you heat this ice, it will melt soon” (first—specific prediction). Zero conditional works for scientific laws, mechanical processes, general habits, and cause-effect relationships that don’t change.

When NOT to use: Don’t use zero conditional for one-time events or uncertain outcomes. “If it rains tomorrow, the picnic is cancelled” needs first conditional because we’re making a specific prediction, not stating a general truth. Zero conditional describes patterns, not particular instances.

More Examples

Science: “If plants don’t get sunlight, they die.” (Biological fact, always true.)

Technology: “If you press this button, the machine starts.” (How it works every time.)

Personal habit: “If I drink coffee after 6 PM, I can’t sleep.” (My consistent pattern.)

Instructions: “If the light turns red, you stop.” (Traffic rule, universal.)

Contrast: “If you study hard, you pass tests” (zero—general truth) vs. “If you study hard, you’ll pass this test” (first—specific prediction about one exam).

Practice & Reflection

Exercises:

  1. Fill in the blank: If you _ (add) vinegar to baking soda, it _ (fizz).

  2. Correct the mistake: “If I will exercise regularly, I feel better.”

  3. Choose and explain: Which is zero conditional?
    a) “If it rains tomorrow, we’ll cancel the hike.”
    b) “If it rains, the grass gets wet.”

  4. Rewrite: Transform “Heating metal causes it to expand” into a zero conditional sentence.

  5. Compare: Explain the difference between “If you touch fire, you get burned” and “If you touch that fire, you’ll get burned.”

  6. Your reflection: Write a zero conditional sentence about a scientific fact or personal habit you’ve observed to be consistently true.

Answer Key:
1. add, fizzes (both present simple—scientific fact)
2. “If I exercise regularly, I feel better.” (Remove ‘will’ from the if-clause; zero conditional uses present in both clauses.)
3. (b) is zero conditional (general truth). (a) is first conditional (specific future prediction).
4. “If you heat metal, it expands.” (Present simple in both clauses.)
5. First = general law (always). Second = specific situation (this particular fire, right now).
6. Check: Do both clauses use present simple? Does it describe something always true? Example: “If I skip breakfast, I get a headache by noon.”

The Lesson

Luna rewrote: “If you heat water to 100°C, it boils.” The Professor smiled. “Zero conditional trusts the universe’s consistency. No ‘will,’ no ‘might’—just pure cause and effect. Faraday taught that if you understand how nature works, you can predict it perfectly.” Luna nodded. Some truths don’t need future tense. They exist, unchanging, waiting to be discovered.