6 Most VSAQ’s of Chemical Equations Chapter in Class 10th Physical Science (TS/AP)

2 Marks

VSAQ-1 : Balance the following chemical equation.
Al+Fe₂O₃→Al₂O₃+Fe

$$2\text{Al} + \text{Fe}_2\text{O}_3 \rightarrow \text{Al}_2\text{O}_3 + 2\text{Fe}$$

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VSAQ-2 : Balance the following chemical equation.

Na+H₂O→NaOH+H₂

Balanced Chemical Equation:

1. Unbalanced Equation:
   $$\text{Na} + \text{H}_2\text{O} \rightarrow \text{NaOH} + \text{H}_2$$
2. Balanced Equation:
   • $$2\text{Na} + 2\text{H}_2\text{O} \rightarrow 2\text{NaOH} + \text{H}_2$$
   • In this reaction, 2 atoms of sodium (Na) react with 2 molecules of water (H₂​O) to form 2 molecules of sodium hydroxide (NaOH) and 1 molecule of hydrogen gas (H₂​).

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VSAQ-3 : Na₂SO₄+BaCl₂→BaSO₄+NaCl. Do the atoms of each element on the left side equal to the atom of the element on the right side of the equation?

Equation Balancing:

1. Original Equation:
   $$\text{Na}_2\text{SO}_4 + \text{BaCl}_2 \rightarrow \text{BaSO}_4 + \text{NaCl}$$
2. Balanced Equation:
   • $$\text{Na}_2\text{SO}_4 + \text{BaCl}_2 \rightarrow \text{BaSO}_4 + 2\text{NaCl}$$
   • In the balanced equation, atoms of each element on the left side are now equal to the atoms of the same element on the right side.

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VSAQ-4 : Mention the chemical equation of reaction between the Mg and O₂ and write its physical state of reactants and products.

Chemical Equation and Physical States:

1. Equation:
   $$2\text{Mg} + \text{O}_2 \rightarrow 2\text{MgO}$$
2. Physical States of Reactants and Products:
   • Magnesium (Mg): Solid
   • Oxygen (O₂): Gas
   • Magnesium Oxide (MgO): Solid

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VSAQ-5 : How do we know that a chemical reaction has taken place?

Indicators of Chemical Reactions:

1. Change in State and Color: Observable when substances transform from one state (solid, liquid, gas) to another or exhibit a noticeable color change.
2. Change in Temperature: A significant increase or decrease in temperature during the reaction, indicating energy changes.
3. Formation of Precipitate: Occurs when two solutions mix and an insoluble solid (precipitate) forms.
4. Liberation of Gas: The production of gas bubbles or a noticeable release of gas during the reaction.

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VSAQ-6 : If you keep an iron piece in solid state CuSO₄ crystals, does it get any reaction? Guess the reason.

Chemical Interaction:

1. Situation: Iron piece placed in solid-state CuSO4 crystals.
2. Reaction Occurrence: Typically, no reaction occurs.
3. Reason for Non-Reactivity:
   • In solid CuSO4 crystals, copper ions (Cu²⁺) and sulfate ions (SO4²⁻) are not freely available as separate entities.
   • Chemical reactions generally occur when ions are in solution and can interact with other substances.
   • In an aqueous solution of CuSO₄, the Cu²⁺ ions are in a form that allows iron to displace copper in a redox reaction.
   • However, in the solid state, the ions are not as accessible for such reactions.