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Some Basic Concepts of Chemistry

Long Answer Type

171.

Explain the following terms with examples:
1. Skeleton equation
2. Balanced equation
3. Thermochemical equation.

103 Views

Short Answer Type

172.
What do you mean by 'balancing a chemical equation'? On what principle the balancing of a chemical equation is based?

When the number of atoms of each element are same on both the sides of an equation, it is called a balanced chemical equation. The principle on which the balancing of a chemical equation is based is ‘Law of Conservation of mass’ or Law of Industructibility of matter, which states: Matter can neither be created nor destroyed in any physical or chemical change. Hence, atom that takes part in a chemical reaction can neither be created nor destroyed. Therefore, in a chemical reaction atoms of each element on both the sides of the arrow

must be equal.
For example,

113 Views

Long Answer Type

173.

How are chemical equations balanced? discuss any two.

101 Views

174.

Balance the following equations:
$1. space space space straight H subscript 3 PO subscript 3 space space space rightwards arrow space space space space straight H subscript 3 PO subscript 4 plus PH subscript 3 2. space space space Ca plus straight H subscript 2 straight O space space rightwards arrow space space Ca left parenthesis OH right parenthesis subscript 2 plus straight H subscript 2$

112 Views

175. Translate the following equations into the language of chemistry and balance by hit and trial method:
Magnesium nitride + Water

rightwards arrow

Magnesium hydroxide + Ammonia

101 Views

176.

Balance the following skeleton equation by hit and trial method:
$Fe subscript 3 straight O subscript 4 plus straight H subscript 2 space rightwards arrow space Fe plus straight H subscript 2 straight O$

103 Views

177.

Balance the following skeleton equation by hit and trial method:
$Fe subscript 2 left parenthesis SO subscript 4 right parenthesis subscript 3 plus space NH subscript 3 plus straight H subscript 2 straight O space rightwards arrow space space space Fe left parenthesis OH right parenthesis subscript 3 plus left parenthesis NH subscript 4 right parenthesis subscript 2 SO subscript 4$

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178.

Balance the following skeleton equation:

$NH subscript 3 NI subscript 3 space rightwards arrow space space straight N subscript 2 plus straight I subscript 2 plus NH subscript 4 straight I$

95 Views

179.

Balance the following skeleton equation:

$KMnO subscript 4 plus HCl space rightwards arrow space KCl plus MnCl subscript 2 plus straight H subscript 2 straight O plus Cl subscript 2$

108 Views

180.

Balance the given skeletion equation $straight P subscript 4 plus HNO subscript 3 space rightwards arrow space space straight H subscript 3 PO subscript 4 plus NO subscript 2 plus straight H subscript 2 straight O$ by partial equation method.