Sᴄɪᴇηᴄᴇ Aηᴅ Cᴏᴍᴘᴜᴛᴇʀ Nᴏᴛᴇs™ 🎲

🏝⛲️🏝*MOST IMPORTANT CHEMISTRY QUESTIONS*🏝⛲️🏝 ══════════════════♢.✰.♢════════════════════ 🔺🔺66. Who proposed that atom is indivisible? – Dalton 🔺🔺67. A typical example of a semiconductor is – Germanium 🔺🔺68. What is the maximum number of electrons that a p-orbital can hold – 6 🔺🔺69. What is used in fire extinguisher – Sodium bicarbonate 🔺🔺70. What is the nature of metal oxides – Basic 🔺🔺71. Which gas burns with popping sound – Hydrogen 🔺🔺72. Which metal is used for galvanization – Zinc 🔺🔺73. What is the nature of bleaching powder – Oxidising agent 🔺🔺74. Which is stored in Kerosene – Sodium 🔺🔺75. Phenolphthalein gives which color in acidic medium – Colorless 🔺🔺76. Which gas is used in cigarette lighters? – Butane 🔺🔺77. Biogas chiefly contains __ . – Methane #REVISION #IMPORTANT

🏝🏝⛲️Generations of Computers⛲️🏝🏝 ════════════♢.✰.♢══════════════ ❖◇❖First Generation (1945-1955)❖◇❖ 🔺1. Vacuum Tubes invented 🔺2. Magnetic Drum for memory 🔺3. Works on 4000 bits 🔺4. ENIAC, EDVAC, EDSAC, UNIVAC-I ❖◇❖Second Generation (1955-1965)❖◇❖ 🔺1. Transistors invented by J. Bardeen, H.W. Brattain and W. Shockley 🔺2. Magnetic Core was used for primary storage 🔺3. 32,000 bits 🔺4. IBM 700/7000, 7094, 1401, IBM 650, ATLAS, CDC (Control data Corporation) 1604, 3600, NCR (National cash register)304 ❖◇❖Third Generation (1965-1971)❖◇❖ ◇◇1. IC (Integrated circuits) invented by Jack Kilby and Robert Noyce ◇◇2. 128,000 bits ◇◇3. Multiprogramming ◇◇4. Keyboard, Monitor ◇◇5. IBM 360, 370, PDP (Programmed Data Processor) 8, 11, UNIVAC AC9000 ❖◇❖Fourth Generation (1971-1990)❖◇❖ ◇◇1. LSI, VLSI ◇◇2. 100 Million bits ◇◇3. Microprocessor (4004) ◇◇4. Time sharing, Real time, Distributed and Networks OS were introduced ◇◇5. Apple Macintosh, IBM PC, SUN SPARC, STAR 1000 ❖◇❖Fifth Generation (1990-Till Date)❖◇❖ 🔺🔺1. ULSI, SLSI, AI 🔺🔺2. Robotics, Neural Networks, Expert System 🔺🔺3. Parallel Processing 🔺🔺4. HVD Technique 🔺🔺5. Advancement of Supercomputing 🔺🔺6. Laptop, Desktop, Notebook, Ultrabook, Chromebook #important