चिकित्सा शिक्षा आयोग (CEE) बीडीएस प्रवेश परीक्षा तयारी
चिकित्सा शिक्षा आयोग (CEE) – बीडीएस प्रवेश परीक्षा
CEE – BDS Entrance · Medical Education Commission – CEE
२,०३९ प्रश्न उपलब्ध। मोड छान्नुहोस्:
MBBS/BDS/Nursing प्रवेश: प्रश्न र उत्तर
सही लागेको विकल्पमा थिच्नुहोस्। सही भए हरियो, गलत भए रातो देखिन्छ; ३ सेकेन्डपछि सही उत्तर र व्याख्या देखिन्छ।
सही: ० / ०
-
The colour of most transition metal ions in aqueous solution is due to:
सही उत्तर: ख) d–d electronic transitions
Partially filled d orbitals split in the presence of ligands, and electrons absorb visible light while jumping between them. Ions with d⁰ or d¹⁰ configurations, like Zn²⁺, are usually colourless.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Depletion of the stratospheric ozone layer is mainly caused by:
सही उत्तर: ग) Chlorofluorocarbons (CFCs)
In the stratosphere, UV light breaks CFCs to release chlorine radicals that destroy ozone catalytically. CO₂ and methane are mainly linked to the greenhouse effect.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The most abundant noble gas in Earth's atmosphere is:
सही उत्तर: घ) Argon
Argon makes up nearly 1% of dry air, far more than any other noble gas. Helium is abundant in the universe but scarce in the atmosphere because it escapes into space.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The catalyst used in the Contact process for the manufacture of sulphuric acid is:
सही उत्तर: क) V₂O₅
Vanadium pentoxide catalyses the oxidation of SO₂ to SO₃, the key step of the Contact process. Iron is the catalyst in the Haber process.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The catalyst used in the Haber process for the manufacture of ammonia is:
सही उत्तर: क) Iron (with molybdenum as promoter)
Finely divided iron with Mo (or K₂O/Al₂O₃) promoters catalyses N₂ + 3H₂ ⇌ 2NH₃. V₂O₅ is used in the Contact process for sulphuric acid.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The allotrope of carbon that is a good conductor of electricity is:
सही उत्तर: ख) Graphite
In graphite each carbon is sp² hybridised, leaving one delocalised electron per atom that moves between layers to conduct electricity. In diamond all four electrons form sp³ σ bonds, so it is an insulator.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The chemical name of bleaching powder is commonly given as:
सही उत्तर: ग) Calcium oxychloride, Ca(OCl)Cl
Bleaching powder, made by passing chlorine over dry slaked lime, is represented as Ca(OCl)Cl (CaOCl₂). It releases chlorine, which acts as a bleach and disinfectant.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Sodium carbonate is manufactured industrially by the:
सही उत्तर: ख) Solvay (ammonia–soda) process
The Solvay process uses brine, ammonia and CO₂ to form NaHCO₃, which is heated to give Na₂CO₃. The Castner–Kellner process is used for making NaOH.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The chemical formula of Plaster of Paris is:
सही उत्तर: क) CaSO₄·½H₂O
Plaster of Paris is calcium sulphate hemihydrate; mixed with water it sets back into gypsum, CaSO₄·2H₂O. Anhydrous CaSO₄ is called dead-burnt plaster.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Heavy water (D₂O) is used in nuclear reactors as a:
सही उत्तर: ख) Moderator
D₂O slows down fast neutrons without absorbing many of them, so it acts as a moderator. Neutron-absorbing materials like cadmium or boron are used in control rods.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
यी अभ्यास प्रश्न हुन्, आधिकारिक प्रश्न होइनन्। पाठ्यक्रम, विज्ञापन र नतिजाका लागि सम्बन्धित निकायको आधिकारिक वेबसाइट हेर्नुहोस्। उत्तरमा गल्ती भेटे प्रश्नमुनिको "टिप्पणी / गल्ती रिपोर्ट" मा लेख्नुहोस्।
नमस्ते! पाठ्यक्रम, सामान्य ज्ञान, भाषा परीक्षा वा कुनै प्रश्नको उत्तर बुझ्न सोध्नुहोस्।
AI ले गल्ती गर्न सक्छ। महत्वपूर्ण कुरा आधिकारिक स्रोतमा जाँच्नुहोस्।