The novolac polymer has mass of 963g. The number of monomer units present in it are

<p>Monomer of novolac is</p><p><img ></p><p>Molecular mass of monomer unit</p><p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; = 12 × 7 + 1 × 8 + 16 × 2</p><p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; = 84 + 8 + 32</p><p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; = 124 g</p><p>Molecular mass of polymer = 963 g</p><p><span contenteditable="false"> <math> <mrow> <mo>∴</mo> </mrow> </math> </span> &lt;!- [if gte mso 9]>&lt;xml&gt; <o:OLEObject Type="Embed" ProgID="Equation.DSMT4" ShapeID="_x0000_i1025" DrawAspect="Content" ObjectID="_1815898353"> </o:OLEObject>&lt;/xml&gt;&lt;! [endif]-&gt;n × mass of monomer = mass of polymer + (n – 1) × 18</p><p> (n – 1) unit of H₂O is removed during formation</p><p><span contenteditable="false"> <math> <mrow> <mo>∴</mo> <mn>1</mn> <mn>2</mn> <mn>4</mn> <mo>×</mo> <mi>n</mi> <mo>=</mo> <mn>9</mn> <mn>6</mn> <mn>3</mn> <mo>+</mo> <mn>1</mn> <mn>8</mn> <mrow> <mo> (</mo> <mrow> <mi>n</mi> <mo>−</mo> <mn>1</mn> </mrow> <mo>)</mo> </mrow> </mrow> </math> </span></p><p>106n = 945</p><p><span contenteditable="false">&nbsp;<math> <mrow> <mo>∴</mo> <mi>n</mi> <mo>=</mo> <mfrac> <mrow> <mn>9</mn> <mn>4</mn> <mn>5</mn> </mrow> <mrow> <mn>1</mn> <mn>0</mn> <mn>6</mn> </mrow> </mfrac> <mo>=</mo> <mn>8</mn> <mo>.</mo> <mn>9</mn> <mn>1</mn> <mo>≈</mo> <mn>9</mn> </mrow> </math> </span></p>

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