mineral acids commonly found in the laboratory are hydrochloric acid‚ sulphuric acid and nitric acid. 3. Alkalis taste bitter and feel soapy or slippery. 4. The common alkalis found in the laboratory are sodium hydroxide solution‚ potassium hydroxide solution‚ calcium hydroxide solution and ammonia solution. 10.2 Acid-Alkali Indicators 1. An acid-alkali indicator shows different colours in acids and alkalis. It can be used to test acids and alkalis. 2. Natural indicators can be made
Premium PH Acid Base
Surname Centre No. Initial(s) Paper Reference 4 3 3 5 Candidate No. 2 H Signature Paper Reference(s) 4335/2H Examiner’s use only London Examinations IGCSE Team Leader’s use only Chemistry Paper 2H Higher Tier Wednesday 17 June 2009 – Morning Time: 2 hours Materials required for examination Nil Items included with question papers Nil Question Leave Number Blank 1 2 3 4 5 6 7 8 9 Instructions to Candidates In the boxes above‚ write your centre number‚ candidate number‚ your surname
Premium Oxygen Sulfuric acid Copper
Introduction The major component of eggshells is calcium carbonate (CaCO3). Calcium carbonate cannot be dissolved in water‚ but can dissolve in an acid using the reaction: 2HCl(aq)+CaCO3(s) Ca2+(aq)+CO2(g)+H2O+2HCl-(aq) This reaction is not used to titrate the CaCO3 because it is very slow when the reaction is close to the endpoint. Instead adding an excess of acid to dissolve all of the CaCO3 and then titrating the remaining H3O+ with NaOH solution can achieve the determination of the amount
Premium Titration Calcium carbonate Hydrochloric acid
of the following problems‚ write complete chemical equations to describe the chemical process taking place. Important note: There are a few physical processes on this sheet – You can’t write an equation for a physical process! 1) When lithium hydroxide pellets are added to a solution of sulfuric acid (dihydrogen sulfate)‚ lithium sulfate and water are formed. 2) When dirty water is boiled for purification purposes‚ the temperature is brought up to 1000 C for 15 minutes. 3) If a copper coil
Premium Chlorine Hydrochloric acid Sodium chloride
Stoichiometry Practice Problems Be sure to balance all equations before you start calculating! Answer key is at the end. 1) Lithium hydroxide reacts with hydrobromic acid to produce lithium bromide and water. If you start with ten grams of lithium hydroxide‚ how many grams of lithium bromide will be produced? 2) Ethylene (C2H4 ) reacts with oxygen gas to produce carbon dioxide and water. If you start with 45 grams of ethylene‚ how many grams of carbon dioxide will be produced?
Premium
chloride + Aluminium sulphate → Barium sulphate + Aluminium chloride (iii) Sodium + Water → Sodium hydroxide + Hydrogen Answer (i) (ii) (iii) Question 3: Write a balanced chemical equation with state symbols for the following reactions. (i) Solutions of barium chloride and sodium sulphate in water react to give insoluble barium sulphate and the solution of sodium chloride. (ii) Sodium hydroxide solution (in water) reacts with hydrochloric acid solution (in water) to produce sodium chloride solution
Premium Chemical reaction Oxygen Chlorine
Agents and Bonding Admixtures. It would damage the concrete or occur some reduction in compressive strength. Question 2 (a) -Different burning temperature -Different fineness of grinding -Add the cement powder with other materials‚ i.e. calcium chloride‚ flyash or silica fume‚ to produce special cements. (b) A reaction generates considerable amount of heat and cause the cement stiffen within a few minutes after mixing with water. * Can be overcome by adding water‚ but low overall
Premium Concrete Cement
Grade 11 Chemistry Year End Test Multiple Choice Identify the choice that best completes the statement or answers the question. ____ 1. The molar mass of copper(II) sulfate pentahydrate‚ CuSO4.5H2O‚ is a. 245.6 g/mol d. 241.5 g/mol b. 177.5 g/mol e. 249.6 g/mol c. 219.2 g/mol ____ 2. A 100.0-g sample of a compound is composed of 16.3 g of carbon‚ 32.1 g of chlorine‚ and 51.6 g of fluorine. The empirical formula of the compound is a. CClF d. C3Cl2F6 b. CClF3 e. C9Cl6F18 c. C2Cl2F6 ____ 3. A
Premium Hydrochloric acid Sulfuric acid Sodium chloride
dissolves‚ the concentrations of K+(aq) and HC4H4O6-(aq) will not increase further and any additional KHC4H4O6 added after this point will remain as a solid. At this point‚ the solution is said to be saturated. The rates at which KHC4H4O6 is dissolving and reprecipitating are equal in a saturated solution‚ so that no net change is observed. This process is another example of dynamic equilibrium. The equation for potassium hydrogen tartrate dissolving in water is: KHC4H4O6 (s) K+(aq) + HC4H4O6-(aq)
Premium
drinks right when you need it. Hot-Can is non-toxic and non-flammable‚ and 100% recyclable. 1.How does Hot-Can work? Hot-Can has developed a special double-chambered aluminium can which contains the beverage in the outer chamber and holds water and calcium oxide (quick lime) separately in the inner chamber. When the seal at the bottom of the can is depressed and broken‚ the water mixes with the quicklime‚ starting an exothermic reaction that heats the contents of the outer chamber by 50-55°C in just
Premium Calcium carbonate Carbon dioxide Heat