General Science/Everyday Science MCQs
Topic Notes: General Science/Everyday Science
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
131
As of mid-2025, the High Seas Treaty (BBNJ) needed how many ratifications to enter into force?
Answer:
60
The treaty opens a path to protect biodiversity beyond national jurisdiction and enters into force after 60 ratifications; by June 2025, 49 had ratified. ([High Seas Alliance](https://highseasalliance.org/treaty-ratification/table-of-countries/?utm_source=chatgpt.com "Signature and Ratification Progress Table"))
132
The EU Carbon Border Adjustment Mechanism (CBAM) moves from a transitional reporting phase to paid compliance starting:
Answer:
arbon Border Adjustment Mechanism (CBAM) moves from a transitional reporting phase to paid compliance starting:
From Oct 2023 to end-2025, importers report embedded emissions; certificate purchasing begins in 2026 as free EU ETS allowances are phased down. ([Taxation and Customs Union](https://taxation-customs.ec.europa.eu/carbon-border-adjustment-mechanism_en?utm_source=chatgpt.com "Carbon Border Adjustment Mechanism - European Commission"))
133
The EU Nature Restoration Law (2024) requires Member States to restore at least what share of land and sea by 2030?
Answer:
20%
The adopted regulation sets binding restoration targets—20% by 2030, with longer-term goals through 2040–2050—making it the first continent-wide law of its kind. ([IFAW](https://www.ifaw.org/international/journal/eu-nature-restoration-law-adopted?utm_source=chatgpt.com "EU Nature Restoration Law: Landmark legislation finally ..."))
134
COP29 also advanced Paris Agreement carbon markets by:
Answer:
Approving an Article 6.2 registry service
The Baku conference enabled the UNFCCC Secretariat to provide registry services interoperable with national systems for internationally transferred mitigation outcomes. It was a long-negotiated operational step. ([IISD](https://www.iisd.org/articles/insight/baku-conference-sets-new-collective-climate-finance-goal?utm_source=chatgpt.com "Baku Conference Sets New Collective Climate Finance Goal"))
135
At COP29 (Baku, 2024), parties agreed a new collective climate-finance goal of:
Answer:
USD 300 bn/yr by 2035
COP29 concluded with agreement to triple the previous USD 100 bn pledge to USD 300 bn annually by 2035, alongside an ambition to mobilize USD 1.3 tn/yr from all sources by 2035. Many developing countries said the figure was still short of needs. ([UNFCCC](https://unfccc.int/news/cop29-un-climate-conference-agrees-to-triple-finance-to-developing-countries-protecting-lives-and?utm_source=chatgpt.com "COP29 UN Climate Conference Agrees to Triple Finance ..."))
136
The most climate-friendly refrigerants have:
Answer:
Zero ozone depletion and low GWP
Natural refrigerants (e.g., CO₂, ammonia, hydrocarbons) and HFOs can meet this goal. Safety and efficiency must also be considered. Transition aligns with Kigali Amendment targets.
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Awesome — here are **50 fresh, up-to-date MCQs** on very recent environment & sustainability developments (numbering continues from your last set). Each has a brief explanation, and I’ve cited key facts where recency matters.
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137
“Greenwashing” refers to:
Answer:
Misleading claims of environmental benefits
It undermines trust and misdirects consumers. Standards and third-party verification reduce risks. Transparent, measurable metrics are key.
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138
The primary environmental risk of desalination is:
Answer:
Brine discharge impacting marine life
High-salinity brine can reduce oxygen and harm benthic organisms. Energy use also drives emissions. Diffusers and renewable power mitigate impacts.
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139
The best habitat restoration approach for a degraded mangrove is:
Answer:
est habitat restoration approach for a degraded mangrove is:
Tidal exchange is essential for mangrove health and sediment dynamics. Native species ensure functional recovery. Community engagement improves success.
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140
An environmental KPI that best tracks potable water efficiency is:
Answer:
L/person·day or L/m²·year
Normalizing by occupants or floor area allows meaningful comparison. Trends reveal efficiency improvements or leaks. Benchmarks vary by building type.
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