Telangana SCERT Class 10 Physical Science Chapter 2 Solution – Chemical Equations. Here in this post we provides Class 10 Physical Science Chemical Equations Telangana State Board Solution. Telangana State Board English Class X Medium Students can download this Solution to Solve out Improve Your Learning Questions and Answers.
Telangana State Board Class 10 Physical Science Chapter 2 Chemical Equations Solution:
CHAPTER: – 2
(Chemical Equations)
Exercise: –
Reflections on concepts
1) What information do you get from a balanced chemical equation?
Ans: – From the balanced chemical equation we get the information about the reactants and the product of that reaction and also the type of chemical reaction it is like exothermic or endothermic etc.
2) Why should we balance a chemical equation?
Ans: – The chemical reaction always be balanced as we know that from the conservation of mass that masses always be same after any reaction. And for that any chemical reaction must be balanced.
3) Balance the following chemical equations. (AS1)
(a) NaOH+ H2SO4 –> Na2SO4 +H2O.
Ans: – 2NaOH + H2SO4 —> Na2SO4 + H2O.
(b) KClO3 —> KCl + O2.
Ans: – 2KClO3 —> 2KCl + 3O2.
(c) Hg (NO3)2+ KI —> HgI2+KNO3.
Ans: – Hg(NO3)2 + 2KI —> HgI2 + 2KNO3;
4) Mention the physical states of the reactants and products of the following chemical reactions andbalance the equations. (AS1)
(a) C6H12O6 —> C2H5OH + CO2.
Ans: – Here, C6H12O6 is a solid, C2H5OH is liquid and CO2 is gas.
(b) NH3 + Cl2 —> N2 + NH4Cl.
Ans: – Here, NH3 is gas, N2 is gas ammonium chloride is solid.
(c) Na + 2H2O —> NaOH + H2.
Ans: – Here, Sodium is solid, sodium hydroxide is gas, hydrogen is gas.
Application of Concepts
1) Balance the following chemical equation after writing the symbolic representation. (AS1)
(a) Calcium hydroxide (s) + Nitric acid (aq) —-> Water (l) + Calcium Nitrate (aq).
Ans: –Ca(OH)2 + 2HNO3 —-> 2H2O + Ca(NO3)2
(b) Magnesium (s) + lodine (s) —> Magnesium lodine (s)
Ans: – 2Mg + I2 —-> 2MgI.
2) Balance the following chemical reactions including the physical states of the substances and balance chemical equations.
(a) Sodium Hydroxide reacts with Hydrochloric acid to form Sodium Chloride and Water.
Ans: – 2NaOH + 2HCl —–> 2 NaCl + 2H2O.
Here NaOH is in oxide state and HCl is in liquid state whereas the product NaCl is in liquid state and H2O is in liquid.
(b) Barium Chloride reacts with liquid Sodium Sulphate to leave Barium Sulphate as aprecipitate and also form liquid Sodium Chloride.
Ans: – BaCl2 + Na2SO4 —-> BaSO4 + 2NaCl.
Here BaCl2 is in liquid state and Na2SO4 is in solid and barium sulphate is in solid and NaCl is chloride form.
Higher Order Thinking Questions
1.) 2 moles of Zinc reacts with a cupric chloride solution containing 6.023×1022 formula units of CuCl2 Calculate the moles of copper obtained
Zn(s) + CuCl2(aq) —>ZnCl2(aq) + Cu(s)
Ans: –
The mole of CuCl2 is = 6.023 × 10^22/ 6.023×10^23=0.1.
So, molar value of CuCl2= 0.1.
The 1 mole of CuCl2 and 1 mole of zinc after mixing with them produces same no of copper. So here as 0.1 mole of CuCl2 after mixing with the zinc produced the same no mole of copper.
2) 1 mole of propane (C3H8) on combustion at STP gives ‘A’ kilo joules of heat energy.Calculate the heat liberated when 2.4 litres of propane on combustion at STP.
Ans: –
As we all know that,
1 mole of any substrates = 22.4liters.
So, 2.4 litres is =2.4/22.4 = 0.10714 mole.
As 1 mole propane in STP contain 1 KJ.
So, the heat liberated is 0.10714 × 1/1 = 0.10714 KJ.
3) Calculate the mass and volume of oxygen required at STP to convert 2.4 kg of graphite into carbon dioxide.
Ans: –
More Important Questions
Q.1) MCQ.
1) The substance undergo chemical change in a reaction are Called……….?
a) Reactants
b) Products
c) Precipitate
d) Gas
2) The symbolic representation of a chemical change is…………?
a) Chemistry
b) Chemical change
c) Chemical reaction
d) Chemical equation
3) The reaction in which heat is observed are called……reaction?
a) Endothermic
b) Exothermic
c) Primary equation
d) None of these
4) ‘Q’ is representation of …………………. in a chemical reaction?
a) Physical state
b) Heat
c) Precipitate
d) Energy
5) The chemical equation before balancing is called………………?
a) Secondary equation
b) Territory equation
c) Skeleton equation
d) None of above
6) In chemical reaction, which of the following is the way of Expressing precipitate formed in a reaction?
a) Upward arrow
b) Downward arrow
c) Horizontal arrow
d) Vertical arrow
Q.2) VERY SHORT ANSWERS.
1) What is the position of reactants in chemical equation?
2) What is the position of product in chemical equation?
3) Give the reaction between Calcium Oxide and water.
4) How do we get to know about precipitate formation in chemical Reaction?
5) What information do we get from a balanced chemical equation.
6) Mention physical states of reactants & products in following Reaction?
7) What is exothermic reaction?
Q.3) SHORT ANSWERS QUESTION.
1) How we should differentiate between chemical change and Physical change?
2) Balance the equation.
C6H12O6 → C2H5OH + CO2
Q.4) LONG ANSWER QUESTION.
1) Calculate volume & mass of hydrogen liberated when 230 g of Sodium reacts with excess of water at STP (atomic no. of
Na = 23 U, O = 16 U, H = 1 U.)
Answer Solution
Q.1) MCQ
1) The substance undergo chemical change in a reaction are Called……….?
a) Reactants
b) Products
d) Gas
2) The symbolic representation of a chemical change is…………?
a) Chemistry
b) Chemical change
c) Chemical reaction
d) Chemical equation
3) The reaction in which heat is observed are called…….reaction?
a) Endothermic
b) Exothermic
c) Primary equation
d) None of these
4) ‘Q’ is representation of …………………. in a chemical reaction?
a) Physical state
b) Heat
c) Precipitate
d) Energy
5) The chemical equation before balancing is called………………?
a) Secondary equation
b) Territory equation
c) Skeleton equation
d) None of above
6) In chemical reaction, which of the following is the way of Expressing precipitate formed in a reaction?
a) Upward arrow
b) Downward arrow
c) Horizontal arrow
d) Vertical arrow
Q.2) VERY SHORT ANSWERS.
1) What is the position of reactants in chemical equation?
→The reactants are written on left hand side of the arrow.
2) What is the position of product in chemical equation?
→ The products are written on right hand side of the arrow.
3) Give the reaction between Calcium Oxide and water.
→ Cao + H2O Ca (OH)2
4) How do we get to know about precipitate formation in chemical Reaction?
→ If precipitate is formed in reaction it is denoted by a downward Arrow.
5) What information do we get from a balanced chemical equation.
→ A balanced chemical equation should give information about Reactants, products and their physical states during reaction.
6) Mention physical states of reactants & products in following Reaction?
→ 1) C6H12O6 → 2C2H5OH + 2CO2
2) C6H12O6 (aq.) → 2C2H5OH (aq.) + 2CO2 (g)
7) What is exothermic reaction?
→The reaction in which heat is given out is called as exothermic reaction.
Q.3) SHORT ANSWERS QUESTION.
1) How we should differentiate between chemical change and Physical change?
→If the nature of original substance would be changed. If new Substance formed during chemical reaction have different Properties to those of original substance. This change is Chemical change and if properties are similar to that of original Substance, then its physical change.
2) Balance the equation.
C6H12O6 → C2H5OH + CO2
→ Step 1: – C6H12O6 → C2H5OH + CO2
Step 2: – No. of atoms
| Element | LHS | RHS |
| C | 6 | 3 |
| H | 12 | 6 |
| 0 | 6 | 3 |
Step 3: – No. of H on LHS is 12. So we have to multiply RHS With 2.
Equation becomes, C6H12O6 → 2C2H5OH +2CO2
Step 4: – To balance Oxygen, multiply with coefficient 2 to CO2.
C6H12O6 → 2C2H5OH +2CO2
This is the balance chemical equation.
Q.4) LONG ANSWER QUESTION.
1) Calculate volume & mass of hydrogen liberated when 230 g of Sodium reacts with excess of water at STP (atomic no. of Na = 23 U, O = 16 U, H = 1 U.)
