Unit 7 Contemporary Issues in Science - Question 1

Oct 3

4 min read

In Unit 7, one of the exam questions typically asks you to “discuss the implications of the scientific issue identified in the articles” (12 marks).

That means you need to go beyond mere description. You are expected to:

Identify the scientific issue(s) raised by the article
Explain the science behind them (processes, mechanisms, constraints)
Discuss the implications — how this scientific issue affects society, environment, economy, policy, ethics, etc.
Use evidence (from the article + your prior scientific knowledge) to support your points
Make reasoned judgements or recommendations (e.g. “this is promising, but further research is needed”)

In short: science + implications + evaluation.

Here's how to plan your answer

Section	Approx weight	Purpose
Introduction / identification	1–2 marks	State the scientific issue, context, define key terms
Science / mechanism explanation	3–4 marks	Explain how it works, the constraints, the challenges
Implications (multiple dimensions)	4–5 marks	Environmental, economic, social, technical, policy, risks
Evaluation, limitations, recommendations	1–2 marks	Strengths, uncertainties, what further research is needed
Conclusion / summary	(~1 mark)	Tie together your discussion in a concise way

Example application: Green Hydrogen

(Background information was drawn from Iberdrola’s green hydrogen article. This blog re-frames the content for BTEC Applied Science Unit 7 exam preparation.)

Let's walk through how you might answer that 12-mark question using the Iberdrola article on green hydrogen.

1. Introduction / identification of the issue

First, you’d begin by summarising the article’s focus, and clearly identify the key scientific issue.

The article discusses green hydrogen: hydrogen produced by the electrolysis of water powered by renewable energy sources rather than fossil fuels. This is a contemporary scientific/technological issue relevant to energy production.

You might define “electrolysis,” and explain the term "green" in the phrase “green hydrogen,” to show you understand the baseline.

2. The science / mechanism & constraints

Here you explain how green hydrogen works, and where challenges lie.

Electrolysis reaction:

Energy must be supplied (electrical energy) to break O–H bonds in water molecules.
Renewable energy input: The key is that the electricity comes from renewable sources (wind, solar, hydro), so the process is low-carbon.
Efficiency losses: Electrolysis is not 100 % efficient — some energy is lost as heat.
Storage and transport issues: Hydrogen is a light gas, difficult to compress and store.

By explaining these, you show depth of scientific understanding.

3. Implications — exploring different dimensions

This is the heart of the 12-mark answer. Here are several angles you could discuss, with examples drawn from the article + your own knowledge.

a) Environmental / climate implications

Reduction in greenhouse gas emissions: Green hydrogen offers a pathway to produce hydrogen without CO₂ emissions (if done using fully renewable electricity). This helps decarbonise sectors (e.g. industry, transport) that are otherwise hard to electrify.

b) Economic / cost implications

Current costs: Green hydrogen is currently more expensive than conventional hydrogen (from natural gas, etc.). The article mentions the cost gap and how scale and technology improvements can reduce costs.
Infrastructure investment: To roll out green hydrogen at scale needs huge capital investment in electrolysis facilities, hydrogen storage, transport pipelines or conversion to other carriers (ammonia, liquid hydrogen), and distribution networks

c) Technical / engineering challenges

Safety concerns: Hydrogen is flammable, has a wide explosive range, is very diffusive (leaks easily). Safety engineering must be rigorous.

d) Social, policy, and ethical implications

Policy/regulation: Governments may need to set standards, safety regulations, subsidies, carbon pricing, or mandates to encourage green hydrogen adoption.
Public acceptance: Hydrogen infrastructure (fuel stations, pipelines) might face public resistance for safety or aesthetic reasons.
Transition risks: The green hydrogen transition could disrupt existing industries (e.g. fossil fuel sectors), leading to job losses unless retraining is supported.

4. Evaluation and recommendations

At this stage, show your ability to make judgements, weigh pros/cons, and suggest what could be done.

The potential of green hydrogen is very promising, especially for decarbonising sectors that are hard to electrify (heavy industry, long-range transport).
However, the high costs, technological risks and infrastructure demands are strong limiting factors.

5. Short conclusion

Wrap up by summarising your argument and reaffirming the key point.

In conclusion, green hydrogen presents a scientifically robust route to low-carbon hydrogen production, with multiple positive implications for climate mitigation, economic growth, and energy security. But significant scientific, technical, economic and policy challenges remain. Only through continued innovation, investment, and coordinated policy support can its full potential be realised.

To score high, your answer should:

Use correct scientific terminology (electrolysis, catalysts, efficiency, etc.).
Integrate knowledge from other parts of your course (chemistry, physics, environmental science) — don’t rely solely on the article.
Show breadth and depth: cover at least 3 dimensions of implications (e.g. environmental, economic, social), and explore them in some depth.
Make reasoned judgments and suggest future directions or recommendations.
Use evidence or data from the article when possible (e.g. cost trends, technical claims) and refer back to it to support your points.