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प्रश्न
Explain the terms with examples.
Balanced equation
उत्तर
A balanced equation is an equation for a chemical reaction in which the number of atoms for each element in the reaction and the total charge are the same for both the reactants and the products. In other words, the mass and the charge are balanced on both sides of the reaction.
The balanced equation is:
2 Fe2O3 + 3 C → 4 Fe + 3 CO2
Both the left and right sides of the equation have 4 Fe, 6 O, and 3 C atoms. When you balance equations, it's a good idea to check your work by multiplying the subscript of each atom by the coefficient. When no subscript is cited, consider it to be 1. It's also good practice to cite the state of matter of each reactant. This is listed in parentheses immediately following the compound. For example, the earlier reaction could be written as:
2 Fe2O3(s) + 3 C(s) → 4 Fe(s) + 3 CO2(g)
where s indicates a solid and g is a gas state of matter.
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संबंधित प्रश्न
Translate the following statement into chemical equation and then balance it.
Hydrogen gas combines with nitrogen to form ammonia
Write the balanced chemical equation for the following reaction.
\[\ce{Calcium hydroxide + Carbon dioxide → Calcium carbonate + Water}\]
2 mL of sodium hydroxide solution is added to a few pieces of granulated zinc metal taken in a test tube. When the contents are warmed, a gas evolves which is bubbled through a soap solution before testing. Write the equation of the chemical reaction involved and the test to detect the gas. Name the gas which will be evolved when the same metal reacts with dilute solution of a strong acid.
Translate the following statement into chemical equation and then balance the equation:
Carbon disulphide burns in air to give carbon dioxide and sulphur dioxide.
Translate the following statement into chemical equation and then balance the equation:
Barium chloride reacts with zinc sulphate to give zinc chloride and barium sulphate.
What is meant by chemical reaction? Explain with the help of an example.
The chemical reaction between quicklime and water is characterised by:
(a) evolution of hydrogen gas
(b) formation of slaked lime precipitate
(c) change in temperature of mixture
(d) change in colour of the product
The metal M reacts vigorously with water to form a solution S and a gas G. The solution S turns red litmus to blue whereas gas G, which is lighter than air, burns with a pop sound. Metal M has a low melting point and it is used as a coolant in nuclear reactors.
(a) What is metal M?
(b) What is solution S? Is it acidic or alkaline?
(c) What is gas G?
(d) Write a balanced chemical equation for the reaction which takes place when metal M reacts with water.
(e) Is this reaction exothermic or endothermic?
The removal of oxygen from a substance is called:
(a) oxidation
(b) corrosion
(c) reduction
(d) rancidity
A colourless lead salt, when heated, produces a yellow residue and brown fumes.
(a) Name the lead salt.
(b) Name the brown fumes.
(c) Write a chemical equation of the reaction involved.
Write symbolic representation for the following word equation and balance them :
Calcium oxide + Water → Calcium hydroxide
Balance the following equation :
Pb3O4 → PbO + O2
Balance the following equation. Also name the product formed.
`"NaNO"_3 → "NaNO"_2 + "O"_2` Name of product (s)
Balance the following equation. Also name the products formed.
`"Mg" + "O"_2 → "MgO"`
Write your observation and name the product when ron nails are added to an aqueous solution of copper sulphate.
Dry raisins were soaked in water for 2 hours, to determine the percentage of water absorbed by raisins. Before final weighing of swollen raisins, the extra water left on the surface of soaked raisins was removed by:
Balance the equation stepwise.
H2S2O7(l) + H2O(l) → H2SO4(l)
Write the chemical equation for the following word equation and balance them.
Magnesium + Sulphuric acid → Magnesium sulphate + Hydrogen
Balance the following equation:
Fe + H2O → Fe3O4 + H2
Write the balanced chemical equation of the following reaction.
silver nitrate → silver + nitrogen dioxide + oxygen
Write the balanced chemical equation of the following reaction.
aluminium + sodium hydroxide + water → sodium meta aluminate + hydrogen
\[\ce{MnO2 + 4HCl -> MnCl2 + 2H2O + Cl2}\]
0.02 moles of pure MnO2 is heated strongly with conc. HCl. Calculate the volume of chlorine gas formed at S.T.P.
(a) Give only one suitable chemical test to identify the following gases.
- Ammonia
- Sulphur dioxide
- Hydrogen Chloride
- Chlorine
- Carbon Dioxide
- Oxygen
- Hydrogen
(b) Select a basic gas mentioned in Q.1 (a). How is the basic nature suspected?
(c)Select acidic gases from the gases mentioned in Q.1 (a). How is the acidic nature suspected?
(d) State the gas responsible for bleaching action.
(e)Which gas turn blue cobalt chloride paper light pink?
Answer the following question.
What is observed when 2 mL of dilute hydrochloric acid is added to 1 g of sodium carbonate taken in a clean and dry test tube? Write a chemical equation for the reaction involved.
When a potassium iodide solution is added to a solution of lead (II) nitrate in a test tube, a precipitate is formed.
Write the balanced chemical equation for this reaction.
In certain reaction an insoluble solid called precipitate is formed. State the colour and name of the precipitate formed in the following reaction involving addition of:
Copper [II] sulphate to sodium hydroxide.
Give one example in the case where supplying energy [given below] is necessary for a chemical reaction.
Electrical energy
Give one example in the case where supplying energy [given below] is necessary for a chemical reaction.
Pressure
Write word equation for the following chemical reaction given below. Also state the observation seen in the case.
Pb(NO3)2 + 2NH4OH → 2NH4N03 + Pb(OH)2↓
\[\ce{2KClO3->[MnO2] 2KCl + 3O2[g] - is a balanced equation.}\]
State why the compound MnO2 is written above the arrow.
Balance the following simple equation:
Al + N2 → AlN
Balance the following simple equation:
NO + O2 → NO2
Balance the following simple equation:
CO2 + C → CO
Balance the following simple equation:
Mg + CO2 → MgO + C
With reference to a chemical equation state which of the statements 1 to 5 pertain to A or B.
A: Information provided by a chemical equation.
B: Limitations of a chemical equation.
- The nature of the individual elements.
- The speed of the reaction.
- The state of matter in which the substance is present.
- The completion of the reaction.
- The direction of the reaction.
Underline the compound in the equation given below, it is incorrectly balanced and write the correct balancing for the same.
Na2SO3 + HCl → 2NaCl + H2O + SO2
Underline the compound in the equation given below, it is incorrectly balanced and write the correct balancing for the same.
Cl2 + 2H2O + SO2 → 4HCl + H2SO4
Underline the compound in the equation given below, it is incorrectly balanced and write the correct balancing for the same.
3CuO + NH3 → 3Cu + 3H2O + N2
Balance the given chemical reaction as per the instructions below.
\[\ce{NaOH + H2SO4 -> Na2SO4 + H2O}\]
Write the number of atoms of various elements in the reactants and products.
Dil. HCl is added to Zn granules. How will you prove that chemical change has taken place here? Support your response with two arguments.
