Chemistry 8 Lesson 43: Prepare solutions 1. Theoretical Summary 1.1. How to prepare a solution according to a given concentration First of all, what is the solute and solvent? There are 2 types of preparation: - Prepare the solution according to the concentration - Prepare solution according to molarity Exercise 1: From CuSO . salt4, distilled … [Read more...] about Chemistry 8 Lesson 43: Prepare solutions
Grade 8 Chemistry
Chemistry 8 Lesson 42: Solution concentration
Chemistry 8 Lesson 42: Solution concentration 1. Theoretical Summary 1.1. Percentage concentration of the solution a) Definition The percentage concentration (C%) of a solution tells us the number of grams of solute present in 100 grams of solution. The formula for calculating the percentage concentration of a solution: \(C\% = … [Read more...] about Chemistry 8 Lesson 42: Solution concentration
Chemistry 8 Lesson 41: Solubility of a substance in water
Chemistry 8 Lesson 41: Solubility of a substance in water 1. Theoretical Summary 1.1. Soluble and insoluble matter a) Test on the solubility of the substance - Experiment 1: Dissolve sand and salt in water Comment: Salt dissolves well in water, sand is insoluble in water. Conclusion: Some are soluble and some are insoluble in water. - Experiment … [Read more...] about Chemistry 8 Lesson 41: Solubility of a substance in water
Chemistry 8 Lesson 40: Solutions
Chemistry 8 Lesson 40: Solutions 1. Theoretical Summary 1.1. Solvent - Solvent - Solution a) Experiment 1: Dissolving sugar in water, we get a sugar water solution Comment: Sugar crystals dissolve in water to form a transparent solution that cannot be distinguished from sugar or water. Conclusion: + Solute: Sugar + Solvent: Water + Solution: … [Read more...] about Chemistry 8 Lesson 40: Solutions
Chemistry 8 Lesson 39: Exercise 6
Chemistry 8 Lesson 39: Exercise 6 1. Theoretical Summary 1.1. Experiment purpose - Practice experimental skills - Understand the chemical properties of water - Research the experiments, complete the test report 1.2. Experimental skills - Experiments are only allowed in the presence of teachers in the laboratory. - Read the instructions … [Read more...] about Chemistry 8 Lesson 39: Exercise 6
Chemistry 8 Lesson 38: Exercise 7
Chemistry 8 Lesson 38: Exercise 7 1. Theoretical Summary a. Chemical composition water quality including hydrogen and oxygen; Mass ratio: H - 1 part, O - 8 parts b. Country react with some metals at normal temperature (such as Na, K, Ca...) to form soluble bases and hydrogen; React with some basic oxides to produce soluble bases such as NaOH, KOH, … [Read more...] about Chemistry 8 Lesson 38: Exercise 7
Chemistry 8 Lesson 37: Acid Base Salt
Chemistry 8 Lesson 37: Acid Base Salt 1. Theoretical Summary 1.1. Acid a. concept An acid molecule consists of one or more hydrogen atoms bonded to an acid base, which can be replaced by metal atoms. b. Formula of acid Recipe: ONLYnA - n: is the index of the H . atom - A: is an acid radical c. Classify - Acids without oxygen: HCl, H2S... - … [Read more...] about Chemistry 8 Lesson 37: Acid Base Salt
Chemistry 8 Lesson 36: Water
Chemistry 8 Lesson 36: Water 1. Theoretical Summary 1.1. Chemical composition of water a. Water decomposition Experiment Install a water electrolysis device (add a little NaOH solution to the water) Video 1: Decompose water with electric current Comment - Before the direct current flows through the water level in two columns A, B are equal. - … [Read more...] about Chemistry 8 Lesson 36: Water
Chemistry 8 Lesson 35: Practice 5
Chemistry 8 Lesson 35: Practice 5 1. Theoretical Summary 1.1. Theoretical purpose - Experimental study on how to prepare hydrogen, how to collect hydrogen gas and test the properties of hydrogen - Master some basic experimental skills 1.2. Experimental skills a. Experiment 1: Preparation of hydrogen gas from hydrochloric acid HCl, zinc Zn. … [Read more...] about Chemistry 8 Lesson 35: Practice 5
Chemistry 8 Lesson 34: Exercise 6
Chemistry 8 Lesson 34: Exercise 6 1. Theoretical Summary a. Hydrogen gas is a reducing agent, at a suitable temperature Hydrogen can not only combine with single oxygen but also with the element oxygen in some metal oxides. These reactions are all exothermic. b. Hydrogen gas has many applications, mainly due to its very light nature (lightest of all … [Read more...] about Chemistry 8 Lesson 34: Exercise 6