Why the early atmosphere is uncertain
Why the early atmosphere is uncertain
Earth formed about 4.6 billion years ago, but almost no direct evidence from that time survives. Scientists therefore use theories to explain the early atmosphere rather than treating its composition as proven fact.
Step-by-step lessons on AQA GCSE Chemistry 9.1.2 The Earth's early atmosphere. Each one builds up to exam-style questions. Nail the core quantitative topics — moles, balancing equations and calculations — early on, since they underpin higher-tier questions across every paper and topic.