Top Class 10 Science Chemical Reactions & Equations: Essential Questions & Answers 📚

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CLASS 12 1 MONTH SYLLABUS COMPLETE STRATEGY-
https://youtu.be/Fye19akA1pM
CLASS 10 1 MONTH SYLLABUS COMPLETE STRATEGY-
https://youtu.be/oXocTwJmK-U

WINTER STUDY TRICK -https://youtu.be/MVJHicTINnM
STUDY TIPS BY SIMRAN SAHNI: https://www.youtube.com/playlist?list=PLlz6Wm71kc1K-DHSvFWn5idTwuGBEZkoL

CLASS 10 SST BY SIMRAN SAHNI: https://www.youtube.com/playlist?list=PLlz6Wm71kc1I-p06WfqBJVHWkzrVzGQKF

CLASS 10 ENGLISH BY SIMRAN SAHNI: https://www.youtube.com/playlist?list=PLlz6Wm71kc1JdI3stlp-V12OiC7GQ2LbA

CLASS 10 SST REVISION BATCH: https://www.youtube.com/playlist?list=PLlz6Wm71kc1JvcymoVkGPO4hxsL6RWXz3

CLASS 10 SCIENCE MODT IMPORTANT QUESTIONS WITH ANSWERS: https://www.youtube.com/playlist?list=PLlz6Wm71kc1IpJISmWUZA7KDaJBMm79z


Class 12 ENGLISH 2020-21 FULL SYLLABUS: https://www.youtube.com/playlist?list=PLlz6Wm71kc1JAhqScEJiCgfdSjlRkc1mu
CLASS 12 ENGLISH REVISION BATCH: https://www.youtube.com/playlist?list=PLlz6Wm71kc1KCCHJZ4I49qIfgHNicq_4z
INDIAN ECONOMY CLASS12: https://www.youtube.com/playlist?list=PLlz6Wm71kc1Kx8Yd9F43JVLxwunEyJdCJ

CLASS 12 HISTORY BY SIMRAN SAHNI: https://www.youtube.com/playlist?list=PLlz6Wm71kc1ItNze2AXyinKqDLCdokJa5
REVISION+BATCH CLASS12 HISTORY: https://www.youtube.com/playlist?list=PLlz6Wm71kc1IYJYJq-RMrisMzgbVAq9hF


Political Science class 12 2020 by Simran Sahni: https://www.youtube.com/playlist?list=PLlz6Wm71kc1Jl1jBiKHguA0LXExKAqdQ7
CLASS 12 POLITICAL SCIENCE REVISION BATCH: https://www.youtube.com/playlist?list=PLlz6Wm71kc1I-6N9ih1NsF9WD9vpAtKjv

class 12 macro economics: https://www.youtube.com/playlist?list=PLlz6Wm71kc1KfUfRXjookRk9qss1fCeWw







Links to all Chapter of class 10 ENGLISH
Chapter 1 - A Letter to God
https://youtu.be/M8o7MyNC4Fw

Dust of Snow
https://youtu.be/c-iRXX1ORw8

Fire and Ice
https://youtu.be/90D2soWIHjM

Nelson Mandela: Long Walk to Freedom
https://youtu.be/hVQmUdjtLzI
A Tiger in the Zoo
https://youtu.be/iM-d0hgKjLQ

Two Stories about Flying 32
I. His First Flight
https://youtu.be/6iSTowiSkYs

II. Black Aeroplane
https://youtu.be/zCJXBNawzp8

From the Diary of Anne Frank
https://youtu.be/fIflTEnGr2Q
Amanda!
https://youtu.be/ptm1JW0NNCs


The Hundred Dresses–I
https://youtu.be/XB6cnfg_t68

The Hundred Dresses–II
https://youtu.be/CaeXaJzzZqM

A Baker from Goa
https://youtu.be/E9iXTy0I0Kw

Coorg
https://youtu.be/q7iGLqatzRY

III. Tea from Assam
https://youtu.be/Y99a9pjyniU

Madam Rides the Bus
https://youtu.be/m92TrJ25mK4

The Sermon at Benares
https://youtu.be/EJkPZWC_nxg
Chapter 1 - A Triumph of Surgery
https://youtu.be/zuBL_VlCadA

Chapter 2 - The Thief's Story
https://youtu.be/yQEqYl4uz_c

Chapter 5 - Footprints without Feet
https://youtu.be/xFz1CDyfYWU

Chapter 7 - The Necklace
https://youtu.be/BB8-6PbelPg

Chapter 6 - The Making of a Scientist

Chapter 8 - The Hack Driver

Chapter 9 - Bholi



Why does the colour of copper sulphate solution change when an iron nail is dipped in it? Write chemical equation for the reaction involved. AnswerIron is more reactive than copper so it displaces copper from copper sulphate solution and forms iron sulphate, hence the colour of solution changes
Equation: Fe + CuSO4 (aq) → FeSO4 (aq) + CuO

a) Explain the term "rancidity." Name the type of chemical reaction responsible for causing rancidity and define it. (b) Write three methods for preventing rancidity of food.AnswerWe have seen food getting contaminated and having an unpleasant smell if it is left open in summer. In a hot weather, Oil present in food get oxidized and become Rancid. Such food is not recommended for consumption. The food is getting oxidized so the reaction is oxidation reaction.Methods for preventing food from getting oxidized are:-(a) Food is kept in cool place like refrigerator.(b) Packaging should be air tight(c) Antioxidants should be added to food

What happens chemically when quick lime is added to water?

Ans. When quick lime is added to water calcium hydroxide (slaked lime) is formed with a hissing sound and lot of heat is evolved during the reaction. The reaction involved is CaO (s) + H2O(Quick Lime) Ca (OH) 2 (s) + Heat (Shaked Lime)

Why should a magnesium ribbon be cleaned before burning in air?

Ans. Magnesium ribbon is cleaned before burning to remove the protective layer of basic magnesium carbonate from the surface of magnesium ribbon.
Give an example of a double displacement reac।।

Solution:

Reaction Between silver nitrate (AgNO3) and Sodium chloride (NaCl) is an example of double displacement reaction. During the reaction negative and positive ions trade positions as a result in the formation of white silver chloride precipitate. The chemical reaction is given below.

Ag+ + NO3– + Na+ + Cl– → AgCl + Na+ + NO3–