GK: Class 12 General Q&A · Page 66
3,658 free answers on GK (General) for Class 12 students, across CBSE, ICSE and State boards.
Question & Answer
Questions
- GeneralClass 12All
How to balance Ca(OH)2 HCl → CaCl2 H2O
The balanced equation for this acid-base neutralization reaction is Ca(OH)2 + 2HCl → CaCl2 + 2H2O. To balance this equation, begin by recognizing that calcium hydroxide contains two hydroxide ions (OH-) that will each react with one hydrogen ion (H+) from hydrochloric acid to form water. Start with the skeleton equation and identify that calcium chloride (CaCl2) contains two chlorine atoms, meaning you need two HCl molecules on the reactant side. Once you place a coefficient of 2
- GeneralClass 12All
What are great lines
Great lines are memorable, impactful statements that capture complex ideas or emotions in concise, quotable language that resonates long after you hear them. These lines succeed because they express universal truths in fresh ways, using vivid imagery, unexpected word choices, or perfect rhythm that makes them stick in your memory. Great lines appear in literature, speeches, songs, movies, and everyday conversation—they're the sentences that make you pause, think differently about someth
- GeneralClass 12All
Is CaO 2HCl CaCl2 H2O a redox reaction
No, the reaction CaO + 2HCl → CaCl2 + H2O is not a redox reaction—it is an acid-base neutralization reaction classified as a double displacement reaction. In this reaction, calcium oxide (a basic oxide) reacts with hydrochloric acid to produce calcium chloride salt and water, but no electrons are transferred between atoms and no oxidation states change. Calcium remains at +2 oxidation state throughout (it's +2 in both CaO and CaCl2), chlorine remains at -1 (in both HCl and CaCl2),
- GeneralClass 12All
What is a pure friendship
Pure friendship is a connection characterized by genuine care and affection without hidden agendas, romantic complications, or self-serving motivations. In this type of relationship, both people value each other's wellbeing and happiness for its own sake, not for what they can gain from the friendship. Pure friendships operate on honesty, mutual respect, and authentic interest in each other's lives—there's no pretense, no keeping score of favors, and no ulterior motives influencing inte
- GeneralClass 12All
What is a bestie quote
A bestie quote specifically celebrates the unique, irreplaceable nature of your closest friendship—the person who functions as both chosen family and partner-in-crime. These quotes emphasize the depth of understanding between best friends, highlighting qualities like unconditional acceptance, shared history, inside jokes that no one else gets, and the ability to communicate without words. Effective bestie quotes acknowledge that this isn't just any friendship but the relationship where
- GeneralClass 12All
What type of reaction is the following reaction H2CO3 → H2O CO2
The reaction H2CO3 → H2O + CO2 is classified as a decomposition reaction, where carbonic acid breaks down into water and carbon dioxide. This is a thermal decomposition that occurs readily at room temperature because carbonic acid is unstable—it exists only briefly in aqueous solution before spontaneously decomposing into its constituent components. The reaction follows the classic decomposition pattern where one compound (AB) breaks apart into two or more simpler substances (A + B
- GeneralClass 12All
What is a cute caption
A cute caption is a sweet, lighthearted, and often playful text that accompanies a photo or post, designed to evoke warmth, smiles, or affection from your audience. These captions typically feature positive language, gentle humor, or endearing observations about the moment captured in the image. Cute captions work well for everyday moments with friends, pets, partners, or solo photos where you want to convey approachability and positive energy without being overly serious or dramatic. They mi
- GeneralClass 12All
What are 5 love quotes
Five powerful love quotes that capture different dimensions of romantic connection include sentiments about love being an action rather than just a feeling, choosing someone daily through both easy and difficult times, finding home in another person rather than a place, loving someone's flaws as much as their strengths, and recognizing that true partnership means growing together without losing individual identity. These themes resonate because they move beyond superficial romance to address
- GeneralClass 12All
What are good friendship quotes
Good friendship quotes capture the essence of meaningful connections through memorable, relatable words that celebrate loyalty, trust, and shared experiences. The most effective friendship quotes resonate because they reflect universal truths about companionship—whether it's the comfort of having someone who accepts you unconditionally, the joy of shared laughter, or the security of knowing someone has your back. Classic examples include sentiments about friends being the family we choo
- GeneralClass 12All
What is friendship one line
Friendship in one line is the voluntary bond between people who choose to support, understand, and genuinely care for each other beyond obligation or blood relation. This relationship centers on mutual trust, shared experiences, and the comfort of being yourself without pretense or judgment. True friendship means having someone who celebrates your successes without envy, stands by you during failures without abandoning you, and values your presence in their life as much as you value theirs.</
- GeneralClass 12All
How do I caption my friend
Caption your friend by highlighting a specific quality, memory, or inside joke that makes your relationship unique and authentic. The strongest friend captions combine genuine affection with personality—reference a shared adventure, celebrate their specific traits (like their infectious laugh or unwavering support), or playfully acknowledge something only the two of you understand. Think about what makes this friend irreplaceable to you, then express it conversationally, as if you're ta
- GeneralClass 12All
Can you explain what is happening in the equation 6CO2 6H2O → C6H12O6 6O2
The equation 6CO2 + 6H2O → C6H12O6 + 6O2 represents photosynthesis, the process by which plants, algae, and some bacteria convert carbon dioxide and water into glucose and oxygen using light energy. In this endothermic reaction, light energy (typically from the sun) is absorbed by chlorophyll and used to break apart the stable bonds in CO2 and H2O molecules, then reassemble those atoms into the higher-energy glucose molecule while releasing oxygen as a byproduct. Essentially, plants are
- GeneralClass 12All
For which reaction is 6CO2 6H2O → C6H12O6 6O2 the correct equation
The equation 6CO2 + 6H2O → C6H12O6 + 6O2 is the correct overall chemical equation for photosynthesis, the light-dependent process by which autotrophic organisms (primarily green plants, algae, and cyanobacteria) convert inorganic carbon dioxide and water into organic glucose and oxygen. This equation specifically represents oxygenic photosynthesis—the type that produces oxygen as a byproduct and occurs in chloroplasts where chlorophyll captures light energy to drive the reaction. W
- GeneralClass 12All
What type of reaction is 6CO2 6H2O → C6H12O6 6O2
The reaction 6CO2 + 6H2O → C6H12O6 + 6O2 is classified as an endergonic synthesis reaction (or anabolic reaction) and specifically as a photosynthetic reduction-oxidation (redox) reaction. This is a combination reaction in the broadest sense, as multiple reactants unite to form more complex products, but it's distinguished by requiring substantial energy input—in this case, light energy absorbed by chlorophyll. The reaction is endothermic and non-spontaneous, meaning it will not oc
- GeneralClass 12All
What type of reaction is Ca 2H2O → Ca(OH)2 H2
The reaction Ca + 2H2O → Ca(OH)2 + H2 is classified as a single replacement reaction (single displacement reaction), where calcium metal displaces hydrogen from water molecules. In this reaction, elemental calcium replaces hydrogen in water, resulting in calcium hydroxide and hydrogen gas as products. This is also simultaneously a redox reaction: calcium is oxidized (loses electrons, going from 0 to +2 oxidation state) while hydrogen is reduced (gains electrons, going from +1 in water to
- GeneralClass 12All
Is CuO(H2) → Cu(H2O) a redox reaction
Yes, the reaction CuO + H2 → Cu + H2O is definitely a redox reaction, involving the transfer of electrons between copper and hydrogen. In this reaction, copper is reduced—it goes from a +2 oxidation state in copper(II) oxide (CuO) to 0 in elemental copper metal (Cu)—meaning it gains electrons. Simultaneously, hydrogen is oxidized—it goes from 0 in H2 gas to +1 in water (H2O)—meaning it loses electrons. This electron transfer is the defining characteristic of all r
- GeneralClass 12All
What happens when you mix calcium oxide and water
When you mix calcium oxide and water, an immediate and highly exothermic chemical reaction occurs, producing calcium hydroxide and releasing intense heat—enough to bring water to boiling temperatures. The reaction CaO + H2O → Ca(OH)2 is so energetic that it can cause the water to steam, the mixture to bubble and froth, and the solid quicklime to expand, crack, and break apart into smaller particles. If you add a large amount of CaO to water at once, the heat generated can be danger
- GeneralClass 12All
How to balance HNO3 Ca(OH)2 → Ca(NO3)2 H2O
The balanced equation for this acid-base neutralization reaction is 2HNO3 + Ca(OH)2 → Ca(NO3)2 + 2H2O. To balance this equation, start by recognizing that calcium hydroxide contains two hydroxide ions (OH-) that need to react with hydrogen ions from nitric acid to form water. First, notice that the product calcium nitrate has two nitrate groups (NO3)2, meaning you need two nitric acid molecules on the reactant side to provide these groups. Once you place a coefficient of 2 before
- GeneralClass 12All
What is the porosity of CaO
The porosity of calcium oxide (CaO) varies significantly depending on its production method, calcination temperature, and source material, but typically ranges from 30% to 60% for quicklime produced from limestone. Porosity refers to the volume fraction of void spaces within the material—essentially how much empty space exists between the solid particles. CaO produced at higher calcination temperatures (around 1000-1100°C) tends to have lower porosity and larger pore sizes, while Ca
- GeneralClass 12All
What is a reducing agent of the reaction Cu2+ Zn → Cu Zn2+
In the reaction Cu2+ + Zn → Cu + Zn2+, zinc (Zn) is the reducing agent. The reducing agent is the substance that causes reduction in another species by donating electrons—and in doing so, the reducing agent itself becomes oxidized. In this case, zinc metal donates electrons to copper ions, enabling the Cu2+ ions to be reduced to neutral copper metal (Cu), while the zinc itself is oxidized from Zn0 to Zn2+. Understanding reducing agents requires recognizing that they are ele