Sciece and Technology Point

 Which alcohol is used in Homeopathic medicine ? In Homeopathic medicine Ethyl alcohol ( also known as Ethanol)  is used.    It is worth to mention that the alcohol used in Rubbing solution is different from the alcohol used in Homeopathic medicine.  In liquor Ethyl alcohol is used. But concentration is different. N.B: Generally in Rubbing solution ( the solution is used for external cleaning in medical set-up) Isopropyl alcohol is used.  How to test the purity of Water?

Purity Test of Purified Water Requirement : Test tube, test tube holder, test tube rack, labeling materials (pen, paper, scissors, gum).  Reagent : Litmus paper (red and blue), BaCl 2 , AgNO 3 , Ammonium Oxalate, NH 4 OH, Nessler's Reagent, Sodium Sulfide, Ingredients: Supplied purified water.  Procedure: Experiment 1: Some amount of purified water is taken in a test tube.  Observation : Clean, colorless, odorless. Inference : May be pure. Experiment 2: Litmus Test: Some amount of purified water is taken in a clean test tube. (a) A blue litmus paper is dipped into the solution. (b) A red litmus paper is dipped into the solution.  Observation : (a) The colour of blue litmus paper is not changed. (b) The colour of red litmus paper is not changed. Inference : (a) Absence of Acid. (b) Absence of alkali. Experiment 3: Some amount of purified water is taken in a test tube. Few ...

Purity test of Sugar of Milk Requirement : Test tube, test tube holder, test tube rack, labeling materials (pen, paper, scissors, gum).  Reagent : Litmus paper (red and blue), Iodine solution.   Ingredients: Sugar of milk and purified water . Procedure: Experiment 1: Some amount of sugar of milk is taken in the fingers and is poured on the tongue. Observation : Colour: milky white Smell: Odorless Taste: Faintly sweet Feeling in touch: Crystalline powder  Inference : May be pure. Experiment 2: Some amount of sugar of milk is taken in a clean test tube. Then, 5 times of its (sugar of milk taken test tube) bulk of water is mixed with it. Then gentle shaking is done until the sugar of milk is fully dissolve.  Observation : Clear odorless solution without any sediment is formed. Inference : May be pure. Experiment 3: Litmus Test: Some amount of sugar of milk is taken in a clean te...

  Friends, today I tell you about a interesting day name " Mole Day ". Interesting, because the timing and date represents a entire scientific number. OK, let's start.  Mole day is celebrated on October 23, between 6:02AM and 6:02PM. It is a day, generally celebrated among scientific community especially, Chemist, Chemistry students and chemistry enthusiasts. Friends, first I tell you what is mole? and then I describe why this date is chosen for Mole day .  What is Mole ? In Science, mole is a unit of substance like Dozen ( a set of twelve). e.g. I can say, "A dozen pens." , "One mole pens."  A dozen = 12 pieces 1 mole = 6.02214076 ✕ 10 23 pieces  The number 6.02214076 ✕ 10 23 is known as Avogadro's number .  In fact, we don't say one mole pens because one mole pen is huge number ( but we can say one mole pens). The unit "mole" is used in Chemistry. Generally, in Chemistry , we frequently use the terms: "1 mole H (Hydro...

  Nowadays, we all use soap for washing, bathing. There are many soaps of various brands available in the market. Some of them claim that they are Herbal, Natural. Have you seen ever the ingredients of the soap, you used daily at bathing, handwashing. Here, we try to aggregate the ingredients of the soaps of various brands commonly used in India. So that, you can compare them easily. In this post we provide the ingredient details of Lifebuoy (Silver Defence +) Lifebuoy (Lemon Fresh) Dettol (Original) Cinthol (Lime Refreshing deo soap) Cinthol Health Soap (Intense Deo Fragrance) Lux (International) Dove  Fiama (gel bar) Himalaya Neem & Turmeric Soap Mysore Sandal Gold Name of ingredients used int he soaps are collected from the packet of that particular soap. We provide the original image of the cover of the soap and image of the site of the cover where the name of ingredients are written. Lifebuoy (Silver Defence +) Ingredients: Sodium Palmate, Sodium Palm Kerne...

Why are Medicines and Chemicals kept in Amber colored Glass bottle? (in Bengali) অ্যাম্বার রঙের কাঁচের বোতল ওষুধ (medicine) এবং রাসায়নিক দ্রব্য (chemicals) এত রং থাকতে, কেন অ্যাম্বার (amber) রং এর কাঁচের বোতলে রাখা হয় তার সম্পূর্ণ উত্তর পেতে গেলে আমাদের দুটো জিনিস খেয়াল করতে হবে 1) কাঁচের বোতল 2) অ্যাম্বার রং এর কাঁচের বোতল এখন আমরা জন্য কাঁচের বোতল কেন ব্যবহার করা হয় কাঁচের বোতল কেন ব্যবহার করা হয়? কাঁচ রাসায়নিকভাবে (chemically) প্রায় নিষ্ক্রিয় (inert) প্রকৃতির। সেইজন্য বেশিরভাগ ওষুধ ও রাসায়নিক দ্রব্যের সঙ্গে কাঁচ কোনরূপ রাসায়নিক বিক্রিয়া করে না।  কাঁচের বোতলের দাম তুলনামূলক ভাবে কম। ফলে প্যাকেজিং এর জন্য খরচ কম হয়।  কাঁচ অনেক সময় ধরে তাপমাত্রা ধরে রাখতে পারে। অর্থাৎ এটি দ্রুত গরম বা ঠান্ডা হয় না। ফলে কোন ওষুধ বা রাসায়নিক দ্রব্যকে যদি ঠান্ডা বা গরম রাখার দরকার হয় তবে কাঁচের বোতল একটি ভালো বিকল্প। কাঁচ ভঙ্গুর প্রকৃতির (যদিও বিভিন্ন কলাকৌশল ব্যবহার করে কাঁচকে অনেক শক্ত বানানো যায়) তা সত্বেও কাঁচের উপরিউক্ত বৈশিষ্টের জন্য ওষুধ ও রাসায়নিক দ্রব্য গুলি কাঁচের বোতলে র...

  In this post we list West Bengal Public Service Commission's previous year CHEMISTRY related questions with detailed solution. Here we arrange previous questions topic wise. This post is Part-2 .    Visit Part-1 .   Actually this is the part of our WBPSC Previous Year Science Series . Under this science series we list and solve WBPSC Previous Year PHYSICS , CHEMISTRY , BIOLOGY, MATHEMATICS and COMPUTER   questions topic wise. Properties of Matter (Acid, Base, Metal, Non-metal, Gas) Q. Which of the following acids can dissolve gold?            [Miscellaneous Exam- 2012(1st)] HNO 3 H 2 SO 4 H 2 SeO 4 HClO 4 Show Answer C. H 2 SeO 4 Explanation: Hot concentrated H 2 SeO 4 (Selenic acid) reacts with gold and can dissolve it. Generally, Aquaregia is used for dissolving gold, platinum.  Aquaregia is a formed by mixing Nitric acid (HNO 3 ) and Hydrochloric acid (HCl) in 1:3 ratio. Q. "Vanish...

  In this post we list West Bengal Public Service Commission's previous year Chemistry related questions with detailed solution. We arrange these questions topic wise. This is Part-1 . Click Here for Part-2 Actually this is the part of WBPSC Previous Year Science Series . Under this we solve the Science Question subject wise. WBPSC Previous Year Physics Question with Answer Part-1 ,  Part-2 ,  Part-3 ,  Part-4 WBPSC Previous Year Computer Questions with Answers Part-1   Environment Q. Which of the following has no greenhouse effect?             [WBPSC Miscellaneous Exam- 2012(1st)] CH 4 N 2 O SO 2 H 2 O Show Answer C. SO 2 Explanation: Here, we assume H 2 O as water vapour. CH 4 (Methane), N 2 O(Nitrous Oxide), water vapour is greenhouse gas. SO 2 (Sulphur dioxide) is not a direct greenhouse gas. It is considered as indirect greenhouse gas because it shows greenhouse effect when coupled with carbon element....

Today we discuss about Chlorine and some most asked questions on Chlorine. Basic Information About Chlorine Chlorine is an element. Its symbol is Cl . Atomic number 17 Molecular formula of chlorine is Cl 2 It belongs to Halogen group of periodic table.   Q. What is the atomic number of Chlorine ? Ans.   Atomic number of Chlorine is 17. (* Atomic number is the number  of proton present in an atom) Q. What is the mass number of Chlorine ? Ans. The mass number of chlorine is 35. (* Mass number = total number of proton and neutrons present in an atom.) Q. How many Chlorine atoms are present in a chlorine molecule ? Ans.   2 chlorine atoms are present in one chlorine molecule.  Q. How many Chlorine molecules are there in 1 mole of chlorine molecule? Ans.   1 mole chlorine molecule contains 6.02214×10 23 chlorine molecule. (6.02214 × 10 23 ) is not an ordinary number. This number is known as Avogadro's Number . 1 m...