What is the need of balance equations? Short answer type questions: 1. In the following. What will be the molecular mass of Ammonia? solution of two ionic compounds react by exchange of their ions is called. (i) A colourless gas which rapidly dissolves in alkaline pyrogallol solution and is a supporter of combustion. or removal of ………. which reactions, addition of oxygen or removal of hydrogen or loss of electron indicates the direction of the reaction. chemical reaction can be observed with the help of any of the following This equation is an example of. reaction is known as endothermic reaction. Give one example of each. If a change involves change in colour or state but no new substance is formed, then it is a ………….. b. A j. Is the burning of a candle wax a physical change or chemical change? When hydrogen gas is passed over heated Y it again changes back into X. How can this black coating be converted into brown copper? b. hand side with a minus sign between them. reaction in which two or more reactants combine to form a single product is I. (a) name the substances X and Y. hydrogen is known as an reducing agent. (a) list any two changes which take place when oily food gets oxidized. Consider the chemical reaction represent by the following equation and write the name of the substance oxidized or reduced, oxidizing agent and reducing agent in the reaction. When When lead nitrate is heated, we could first hear a cracking noise. or gain of electrons takes place. 0 ; nitrogen dioxide. (b)Translate the above statement into a chemical equation. (1)On heating lead nitrate decomposes crackling sound.A Brown Gas,Nitrogen dioxide(NO2) evolves which has irritating smell.The gas turns blue Litmus red,hence Acidic in nature. • (ii) Dissolution of sodium hydroxide in water. Answer the following questions on the basis of observations made by the student: Write a balanced chemical equation for the reaction involved. If you are on a personal connection, like at home, you can run an anti-virus scan on your device to make sure it is not infected with malware. Justify this statement with the help of appropriate chemical equations of each. I. The State the meaning of oxidation in a chemical reaction. A combination reaction is the reverse of a decomposition reaction. Class 10 : Solution of How Do Organism Reproduce? substance gains hydrogen or loses oxygen during a reaction, it is said to be …, 5. n. Rancidity can be prevented by adding ………….. a. Aqueous Identify endothermic or exothermic reactions. List two methods to prevent or slow down the above change. takes place. On treatment with water, it forms a solution that turns red litmus blue. Write a chemical equation. Why decomposition reactions are called the opposite of combination reaction. I. Write the chemical equation for this reaction. C a (O H) 2 + 2 N H 4 C l → C a C l 2 + 2 N H 3 + H 2 O (ii) When sodium nitrite reats with ammonium chloride nitrogen gas is liberated. A solution of substance X is used for whitewashing. CuO + H2 ---> Cu + H2O. Process State two observation which helps us to determine that a chemical reaction has taken place. II. Why do we store silver chloride in dark coloured bottles? Write the chemical equation of the reaction and state its one use. Identify the type of chemical reaction and also write the chemical equation for the reaction that takes place when a solution of potassium chloride is mixed with silver nitrate solution. What is redox reaction? called, 2. Identify X and also write the chemical reactions involved. called, Aqueous Describe an activity to show a decomposition reaction in which light is used to decompose reactants. (iii) Dissolution of ammonium chloride in water. during a reaction, it is said to be oxidised. whereas a ……….. agent gets oxidised. Differentiate between the reaction of magnesium and calcium with water  (giving an example). Write the balanced chemical equations and complete the following reaction and identify the type of reaction. Citric acid. Another way to prevent getting this page in the future is to use Privacy Pass. Identify the substance oxidized and the substance reduced in the reaction. Differentiate between a combination reaction and a decomposition reaction. Is it a chemical or a physical change? Colourless gas with rotten egg smell is evolved. The I. Aqueous solution of sodium sulphate and barium Chloride reacts as follows :ZnSO. (ii) Chlorine gas is passed in an aqueous potassium iodide solution. Name the gas evolved when the following mixtures are heated : (i) Calcium hydroxide and Ammonium Chloride. Solid calcium oxide was taken in a container and water was added slowly to it.