The borax  bead test is used to identify the nature of the cation present in the solution by observing the color of the bead. The color and bead of copper formed during its borax bead test in a hot oxidizing flame and reducing flame

 

 

 

 

 

  All the objects around you, this device, your pen or pencil and things of  nature such as rocks,  water and plant constitute the matter of the universe. Matter is any substance which occupies space and has mass. Dalton, in 1808, proposed that matter was made up of extremely small, indivisible particles called atoms. (In Greek atom means which cannot be cut). This concept  was accepted for number of years. The main postulates of Dalton’s  atomic theory are ·  Matter is made up of small indivisible particles, called atoms. ·  Atoms can  neither  be created nor destroyed. This means that a chemical reaction is just a simple rearrangement of atoms and the same number of atoms must be present before and after the reaction. ·  Atom is the smallest particle of an element which takes part in a chemical reaction. ·  Atoms of the same element are identical in all respects especially, size, shape and mass. ·  Atoms of different elements...

  Parabens are a class of chemicals commonly used as preservatives in personal care and cosmetic products. They are derived from para-hydroxybenzoic acid and are often listed on ingredient labels as methylparaben, ethylparaben, propylparaben, butylparaben, isobutyl paraben, or butylparaben. Parabens are effective at preventing the growth of bacteria and fungi in products, which helps to extend their shelf life and prevent spoilage. However, there has been growing concern over the safety of parabens in recent years, with some studies suggesting that they may have negative health effects. One of the main concerns is that parabens can act as endocrine disruptors, meaning that they can interfere with the normal functioning of hormones in the body. This is because parabens are structurally similar to the hormone estrogen, and may be able to mimic its effects in the body. Some studies have suggested that parabens may be linked to a higher risk of breast cancer, as well as other reproduct...

  Do visit for   video lectures  on important concepts and problems for exam.

Zero-order reactions are chemical reactions that proceed at a constant rate independent of the concentration of the reactants. In this guide, we will derive the expression for the time required for a zero-order reaction and calculate its half-life. Derivation of Time Required for Zero Order Reaction: The rate law for a zero-order reaction is given by: rate = k[R]^0 = k where [R] is the concentration of the reactant and k is the rate constant. We can integrate this rate law to obtain the expression for the time required for a zero-order reaction: [R]t = [R]0 - kt where [R]t is the concentration of the reactant at time t, [R]0 is the initial concentration of the reactant, and k is the rate constant. To solve for time, we can rearrange this equation as: t = ([R]0 - [R]t) / k This is the expression for the time required for a zero-order reaction. Half-Life Calculation: The half-life of a zero-order reaction is the time required for the concentration of the reactant to decrease by half. We ...

  Quiz:Some Basic Concepts of Chemistry Quiz Question 1: A sample of CaCO3 and MgCO3 weighed 2.21 gm is ignited to constant weight of 1.152 gm. What is the composition of the mixture. Also calculate the volume of CO2 evolved at 0°C and 76 cm of pressure.? 539.8 ml 439.8 ml 339.8 ml 239.8 ml Question 2: 0.05 gm of commercial sample of KClO3 on decomposition liberated just sufficient oxygen for complete oxidation of 20 ml CO at 27°C and 750 mm pressure. Calculate % of KClO3 in sample 55.4% 22.5% 65.4% 20% Question 3 : 0.5 gm of fuming H2SO4 oleum is diluted with water.This solution is completely neutralised by 26.7 ml of 0.4 N NaOH. The percentage of free SO3 in the sample is 20.6% 40.6% 30.6% 10.6% Question 4: 34 gm of hydrogen peroxide is present in 1120 ml of solution. This solution will be called 20 volume 10 volume 30 volume 50 volume Question 5: ...

 

  Quiz:Some Basic Concepts of Chemistry Quiz Question 1: What will be the mole fraction of H2SO4 in its aqueous solution with molality 0.1 mol kg^-1? 0.002 0.02 0.01 0.0001 Question 2: What will be the molality of an aq H2SO4 solution if the mole fraction of H2SO4 in this solution is 0.2? 1.389 mol kg-1 1 mol kg-1 13.89 mol kg-1 2 molkg-1 Question 3 : Which of the following concentration term is not temperature dependent? Molarity Mole fraction Normality Mass by volume percentage Question 4: What will be the normality of an aq H2SO4 solution if 9.8 g of H2SO4 is present in 100 ml of solution? 1 2 0.5 3 Question 5: What volume of water must be added to reduce the concentration of aq HCl solution from 0.4 M to 0.1 M if initial volume of solution was 300 ml 900 ml 300 ml 600 ml 100 ml Question 6: Wha...

Quiz:Some Basic Concepts of Chemistry Quiz Question 1: 20 mL of methane is completely burnt using 50 mL of oxygen. The volume of the gas left after cooling to room temperature is? 80 ml 60 ml 30 ml 40 ml Question 2: 10.If 300 mL of a gas weighs 0.368 g at STP. What is its molecular weight? 10.5 g 20.5 g 27.5 g 30 g Question 3 : 61.An organic compound contains C — 40%, H = 13.33% and N = 46.67%. Its emperical formula is? CH4N C2H2N CHN CH2N Question 4: A hydrocarbon on combustion gives 0.88g of CO2 and 0.54 g of H2O, what will be the empirical formula of this hydrocarbon? CH2 CH4 C2H3 CH3 Question 5: If 80 g of CH4 reacts with 160 g of O2 then what amount of CO2 will be formed... 2.5 mol 2 mol 5 mol 10 mol Question 6: If a compound contains 5% sulphur then minimum molecular mass of this compound will be 540 3...

Quiz:Some Basic Concepts of Chemistry Quiz Question 1: What is the smallest part of matter that may have independent existence? Molecule Atom Cation Anion Question 2: Which of the following is the purest form of matter? Element Compound Homogeneous Mixture Heterogeneous mixture Question 3 : Cation is formed when? Electrons are gained Protons are gained Electrons are lost Protons are lost Question 4: Anion is formed when? Electrons are gained Protons are gained Electrons are lost Protons are lost Question 5: Atomic number of an element is equal to the number of ... Protons Neutrons Nucleons Electrons Question 6: Mass number of an element is equal to the number of ... Neutons Protons Electrons Nucleons Question 7: Isotopes contain same number of.... Protons Neutrons Neutron...

  Metallurgical engineering is a branch of engineering that deals with the science and technology of metals and their alloys. It involves the study of the properties and behaviors of metals and how they can be processed, formed, and used in various applications. Metallurgical engineers play a crucial role in the manufacturing industry, as they develop and improve materials used in a wide range of products, from electronics to automobiles. The field of metallurgical engineering is divided into two major areas: physical metallurgy and extractive metallurgy. Physical metallurgy is concerned with the study of the structure and properties of metals and alloys, including their mechanical, electrical, and magnetic properties. Extractive metallurgy, on the other hand, focuses on the processes involved in the extraction and refining of metals from their ores. One of the primary objectives of metallurgical engineering is to understand the behavior of metals under different conditions, such a...

  Petroleum engineering is a field of engineering that involves the exploration, extraction, and production of oil and gas from underground reservoirs. This is a complex and highly technical field that requires a strong understanding of geology, physics, chemistry, and engineering principles. In this article, we will provide a detailed overview of petroleum engineering, including its history, career opportunities, and the skills and education required to succeed in this field. History of Petroleum Engineering Petroleum engineering has been an important field since the early 20th century when oil became a major source of energy for the world. The first oil well was drilled in Pennsylvania in 1859, but it was not until the early 1900s that the petroleum industry really began to take off. With the rise of the automobile industry and the demand for gasoline, petroleum engineers were in high demand to develop new technologies for the exploration and production of oil and gas. Today, pet...

  Marine engineering is a branch of engineering that deals with the design, construction, installation, operation, and maintenance of ships, boats, and offshore structures. It involves a wide range of disciplines, including mechanical, electrical, electronic, and naval architecture, and requires a deep understanding of physics, mathematics, and material science. In this article, we will explore the field of marine engineering in detail. History of Marine Engineering: Marine engineering has a long history, dating back to ancient times when people started building boats and ships for transportation and trade. Over time, as technology advanced, the design and construction of ships became more complex, requiring specialized skills and knowledge. During the Industrial Revolution, marine engineering became a separate field of study, and the development of steam-powered ships marked a significant milestone in the history of marine engineering. Today, marine engineering is a highly special...

  Applied Electronics and Instrumentation Engineering is a branch of engineering that focuses on the design, development, and maintenance of instruments and systems for measuring, monitoring, and controlling various physical parameters such as temperature, pressure, flow, and motion. The field involves the application of electronic, computer, and software technologies to develop systems that improve the efficiency, accuracy, and reliability of industrial processes and scientific research. Some of the areas that Applied Electronics and Instrumentation Engineers work in include industrial automation, robotics, medical devices, communication systems, and control systems for aerospace and defense. They design and implement hardware and software systems to control and monitor the operation of various mechanical and electronic systems. They also develop sensors and transducers to convert physical parameters into electrical signals, which can be analyzed by computer systems to provide rea...