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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?

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

(i) The skeleton equation may be written as

(ii) To equalise the number of Mg atoms, multiply the molecule Mg(OH)₂ by 3.

(iii) To balance the nitrogen atoms, multiply the molecule NH₃ by 2.

(iv) To equalise the number of H and O atoms on both the sides of the above equation, multiply HO by 6.

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:
$Fe subscript 2 left parenthesis SO subscript 4 right parenthesis subscript 3 plus space NH subscript 3 plus straight H subscript 2 straight O space rightwards arrow space space space Fe left parenthesis OH right parenthesis subscript 3 plus left parenthesis NH subscript 4 right parenthesis subscript 2 SO subscript 4$

102 Views

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.