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Earth's History and Geologic Time — 6th Grade Science practice questions

10 multiple-choice questions and 20 flashcards on Earth's History and Geologic Time, about 7% of the 6th Grade Science bank. Every one carries a written rationale.

Written and maintained by Nick Burton · last updated 2026-08-22 · how we write and review questions

What this chapter covers

Earth's History and Geologic Time is one of 5 chapters in CoStudy's 6th Grade Science (Earth Science) bank, and it holds 10 of the bank's 150 multiple-choice questions — roughly 7% of the total. That proportion is not arbitrary: chapters follow the certifying body's published exam outline, and the number of questions in each is set by that domain's published weight, so the share of your practice time this chapter takes matches the share of the real exam it accounts for.

Studying by chapter is worth doing once you have a diagnostic score. A single overall percentage tells you whether you are close; it does not tell you which domain is dragging. Working a weak chapter in isolation, and re-testing it in isolation, is the fastest way to move a score that has stalled — and it is why the mock exams in CoStudy report by domain rather than as one number.

Free Earth's History and Geologic Time practice questions

5 questions drawn from this chapter, with the full rationale shown — the controlling principle behind the right answer, and why each wrong option tempts and fails.

Which is a valid way to display experimental results to find patterns?

  1. Recording numbers without any analysis
  2. Discarding outliers without checking them
  3. Plotting data in a graph and looking for trends
  4. Only reporting results that support the hypothesis

Answer: C — Plotting data in a graph and looking for trends

C) Graphs reveal trends. A) Insufficient. B) Bias risk. D) Cherry-picking.

A hypothesis is BEST described as:

  1. A guaranteed correct answer
  2. The conclusion of an experiment
  3. A random opinion
  4. A testable, predictive statement that can be supported or rejected by evidence

Answer: D — A testable, predictive statement that can be supported or rejected by evidence

D) Standard definition. A) Not guaranteed. B) Hypothesis precedes the result. C) Must be testable, not arbitrary.

Why do scientists repeat experiments multiple times?

  1. Because they enjoy repetition
  2. Only when funding requires it
  3. To use up materials
  4. To establish reliability and reduce the effect of random error

Answer: D — To establish reliability and reduce the effect of random error

D) Replication = scientific reliability. A/B/C) Not scientific reasons.

In an experiment, the INDEPENDENT variable is:

  1. The variable the experimenter changes on purpose
  2. The variable being measured as a result
  3. A variable kept the same
  4. A random factor

Answer: A — The variable the experimenter changes on purpose

A) Independent = manipulated. B) Dependent. C) Control. D) Should be eliminated.

Index fossils help geologists:

  1. Predict tomorrow's weather
  2. Date rock layers, because the species lived during a known limited time span
  3. Locate underwater volcanoes only
  4. Measure the Sun's temperature

Answer: B — Date rock layers, because the species lived during a known limited time span

B) Brief-lived, geographically widespread species → diagnostic ages. A/C/D) Unrelated to fossil utility.

Earth's History and Geologic Time flashcards

4 cards from the 20 in this chapter.

What causes the moon's phases?

As the moon orbits Earth, we see different parts lit by the sun.

Why are some planets so much hotter than others?

Distance from sun matters most. Atmosphere thickness also affects temperature (Venus is super hot due to thick CO₂ atmosphere).

What are some effects of climate change?

Rising temperatures, melting ice, rising seas, more extreme weather, ecosystem disruption.

How long does Earth take to orbit the sun?

One year (365.25 days).

Practise the full chapter

These are a sample. The full Earth's History and Geologic Time chapter runs 30 items with per-chapter progress tracking, on the web and in the iOS app.

Open 6th Grade Science in CoStudy →

Other 6th Grade Science chapters

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