Class 10 Science Chapter 1- Chemical Reactions And Equations

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Class 10 Science NCERT Solution
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Class 10 Science NCERT Solution

• Class 10 Science Chapter 1- Chemical Reactions
  And Equations
• Very interesting chapter of Class 10 Science is
  about chemical reactions and equations. We have
  already studied in Class 9 Science about the
  physical properties of matter. Physical
  properties of matter can change due to melting,
  boiling, and condensation. A Chemical change
  occurs when the nature and the identity of the
  initial substance have somewhat changed. Some
  examples stated below-
• Eg Milk left at room temperature in summers
  becomes sour
• Food get digested in our body.
• This chemical change happens due to chemical
  reaction. We can say if there any of the
  below-mentioned change we can say chemical
  reactions taken place.

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Class 10 Science NCERT Solution

• Change in state
• Change in color
• Evolution of a gas
• Change in temperature
•  
• Class 10 Science students can experiment the
  below in the chemistry lab.
• Activity-
• Take a few zinc granules in a conical flask or a
  test tube
• Add dilute hydrochloric acid or sulphuric acid to
  this
• Do you observe anything happening around the zinc
  granules?
• We Can see Formation of hydrogen gas by the
  action of dilute sulphuric acid on zinc

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Class 10 Science NCERT Solution

•  
• Chemical Equations-
• The symbolic representation of a chemical
  reaction is called a chemical equation. Now the
  question arises how we write these chemical
  equations. Chemical equations can be written in
  chemical formulas instead of writing the chemical
  name in words
• For Eg-
• Magnesium OxygenMagnesium oxide, which can be
  easily written as
• MgO2MgO
• Points to Ponder while writing a chemical
  equation-
• If the number of atoms of each element on the LHS
  and the RHS is same then it is called the
  balanced equation.
• If the atoms are not equal, then the equation is
  unbalanced and it is called the skeleton chemical
  equation

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Class 10 Science NCERT Solution

• Balanced Chemical Equation
•  
• The law of conservation of mass says that mass
  cannot be created nor destroyed in the chemical
  equation. The total elements mass present in the
  products of the chemical reaction has to be equal
  to the total elements mass present in the
  reactants. Eg-
• ZincSulphuric acid Zinc sulphate Hydrogen
  chemical representation of this equation is
• ZnH2SO4ZnSO4H2
• The number of atoms is equal on both the sides so
  this is a balanced equation.

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Class 10 Science NCERT Solution

• How to write a chemical equation?
• To balance a chemical equation, first draw boxes
  around each formula.
• Counting the number of atoms of each element on
  both sides of the equation.
• Start balancing with the compound that contains
  the maximum number of atoms. It may be a reactant
  or a product.
• To check the accuracy of the balanced equation,
  we count atoms of each element on both sides of
  the equation
• To make a chemical equation more informative, the
  physical states of the reactants and products are
  mentioned along with their chemical formulas

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Class 10 Science NCERT Solution

•  
• So, the above-mentioned Class 10 Science
  Notes on chemical equations will clear the
  concepts. For CBSE Exams and NCERT
  Solutions or Class 10, kindly visits
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