Create a custom practice set
Pick category, difficulty, number of questions, and time limit. Start instantly with your own quiz.
Generate QuizGK Questions
Filter by category, type, and difficulty. Reading is open for everyone.
True or False: Alkenes undergo addition reactions due to the presence of pi bonds.
- True
- False
Answer: True
Pi bonds in C=C are weaker and more reactive than sigma bonds, allowing addition of H₂, X₂, HX, etc. Alkanes (only sigma bonds) undergo substitution. Core organic reaction mechanism. [[NCERT Chemistry Class 11]]
The hormone that promotes fruit ripening in plants is ________.
- Auxin
- Gibberellin
- Cytokinin
- Ethylene
Answer: Ethylene
Ethylene is a gaseous plant hormone triggering ripening, senescence, and abscission. Commercially used for artificial ripening of bananas, mangoes. Important for agriculture questions. [[NCERT Biology Class 11]]
Which molecule has a linear geometry?
- H₂O
- NH₃
- CO₂
- CH₄
Answer: CO₂
CO₂ has sp hybridization with two double bonds, resulting in linear shape (180° bond angle). H₂O (bent), NH₃ (pyramidal), CH₄ (tetrahedral). VSEPR theory application. [[NCERT Chemistry Class 11]]
ISRO's launch vehicle that uses cryogenic engines in its upper stage is ________.
- PSLV
- GSLV
- SSLV
- ASLV
Answer: GSLV
GSLV (Geosynchronous Satellite Launch Vehicle) uses indigenous cryogenic upper stage (CE-7.5/CE-20) for launching heavy satellites to GTO. PSLV uses solid/liquid stages. Key for space tech awareness. [[ISRO Reports]]
True or False: A test cross is performed between a dominant phenotype individual and a homozygous recessive individual.
- True
- False
Answer: True
Test cross determines genotype of dominant phenotype: if any recessive offspring appear, the parent is heterozygous. Fundamental tool in Mendelian genetics. [[NCERT Biology Class 12]]
Control rods in nuclear reactors are made of materials that:
- Amplify neutrons
- Absorb neutrons
- Reflect neutrons
- Moderate neutrons
Answer: Absorb neutrons
Control rods (cadmium/boron) absorb excess neutrons to regulate fission chain reaction. Moderators (heavy water/graphite) slow neutrons. Essential for understanding nuclear energy. [[NCERT Physics Class 12]]
True or False: Kaziranga National Park in Assam is a UNESCO World Heritage Site primarily for the Indian one-horned rhinoceros.
- True
- False
Answer: True
Kaziranga (inscribed 1985) hosts ~70% of world's greater one-horned rhinos. It also protects tigers, elephants, and wetland biodiversity. Important for environment and geography exams. [[UNESCO, MoEFCC Reports]]
The spectral series of hydrogen lying in the visible region is called ________ series.
- Lyman
- Balmer
- Paschen
- Brackett
Answer: Balmer
Balmer series (n=2 to higher levels) produces visible lines (Hα, Hβ, etc.). Lyman is UV, Paschen/Brackett are IR. Understanding spectral series is key for atomic structure questions. [[NCERT Physics Class 12]]
True or False: Two-factor authentication (2FA) enhances security by requiring two different types of credentials.
- True
- False
Answer: True
2FA combines something you know (password) with something you have (OTP/app) or something you are (biometric). This layered approach significantly reduces unauthorized access risks. [[CERT-In Guidelines, NCERT Computer Science]]
Jaundice is characterized by yellowing of skin and eyes due to accumulation of ________.
- Urea
- Bilirubin
- Creatinine
- Uric acid
Answer: Bilirubin
Bilirubin, a yellow pigment from hemoglobin breakdown, accumulates in blood due to liver dysfunction, bile duct obstruction, or excessive RBC destruction. Key diagnostic indicator in medicine. [[NCERT Biology Class 11]]
True or False: Modulation is the process of superimposing a low-frequency signal onto a high-frequency carrier wave.
- True
- False
Answer: True
Modulation (AM/FM) enables efficient transmission of audio/video signals over long distances by shifting them to higher frequencies suitable for antenna radiation. Core concept in telecommunications. [[NCERT Physics Class 12]]
The Contact Process is used for the industrial production of ________ acid.
- Nitric
- Hydrochloric
- Sulfuric
- Phosphoric
Answer: Sulfuric
Contact Process oxidizes SO₂ to SO₃ using V₂O₅ catalyst, then absorbs in H₂SO₄ to form oleum. Sulfuric acid is vital for fertilizers, batteries, and chemicals. Important industrial chemistry. [[NCERT Chemistry Class 12]]
True or False: Bryophytes are known as amphibians of the plant kingdom because they require water for fertilization.
- True
- False
Answer: True
Bryophytes (mosses, liverworts) need water for sperm to swim to egg during fertilization, though they live on land. This dual dependency earns them the 'amphibians' title. Key concept in plant evolution. [[NCERT Biology Class 11]]
Which element is commonly used as a dopant to create n-type semiconductors?
- Boron
- Aluminum
- Phosphorus
- Gallium
Answer: Phosphorus
Phosphorus (Group 15) has 5 valence electrons. When doped into silicon (Group 14), the extra electron becomes free for conduction, creating n-type semiconductor. Boron creates p-type. Fundamental for electronics. [[NCERT Physics Class 12]]
Project Tiger was launched in India in the year ________.
- 1971
- 1973
- 1980
- 1992
Answer: 1973
Project Tiger launched on April 1, 1973, to conserve Bengal tigers and their habitats. India now has over 3,000 tigers (2022 census). Landmark conservation initiative. [[NTCA Reports, NCERT Biology Class 12]]
BCG vaccine is given to prevent:
- Polio
- Tuberculosis
- Measles
- Hepatitis B
Answer: Tuberculosis
BCG (Bacillus Calmette-Guérin) vaccine provides immunity against tuberculosis, especially severe forms in children. Part of India's Universal Immunization Programme. [[MoHFW Guidelines, NCERT Biology Class 12]]
The general formula for alkanes is ________.
- CₙH₂ₙ
- CₙH₂ₙ₊₂
- CₙH₂ₙ₋₂
- CₙHₙ
Answer: CₙH₂ₙ₊₂
Alkanes are saturated hydrocarbons with single bonds: CₙH₂ₙ₊₂ (e.g., methane CH₄, ethane C₂H₆). Alkenes: CₙH₂ₙ; Alkynes: CₙH₂ₙ₋₂. Foundational organic chemistry. [[NCERT Chemistry Class 11]]
True or False: 5G networks operate only on high-frequency millimeter waves.
- True
- False
Answer: False
5G uses three spectrum bands: low-band (<1 GHz), mid-band (1-6 GHz), and high-band mmWave (24-47 GHz). Each offers different coverage/speed trade-offs. Important for tech awareness. [[TRAI Reports, NITI Aayog]]
If the distance between two masses is doubled, the gravitational force becomes:
- Half
- Double
- One-fourth
- Four times
Answer: One-fourth
Newton's law: F ∝ 1/r². Doubling distance (r→2r) reduces force to F/4. Inverse-square law applies to gravity, light intensity, etc. [[NCERT Physics Class 11]]
True or False: Oxidation involves gain of electrons.
- True
- False
Answer: False
Oxidation is loss of electrons (OIL: Oxidation Is Loss); reduction is gain of electrons (RIG). Mnemonic helps avoid confusion in redox reactions. [[NCERT Chemistry Class 11]]