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→Example Calculations
===Example Calculations===
{| class="wikitable"
| style="height:20px; width:300px; text-align:center;" |15g of [[Mercury]] requires 4.1J 1kJ of [[energy]] to vaporise. Calculate the [[Specific Latent Heat of Vaporisation|'''specific latent heat''' of vaporisation]] of the [[Mercury]] correct to two [[Significant Figures|significant figures]].
| style="height:20px; width:300px; text-align:center;" |A pan containing 500g of [[water]] at 100°C is [[heat]]ed with an [[energy]] of 1.13kJ until all of the [[water]] has been vaporised. Calculate the [[Specific Latent Heat of Vaporisation|'''specific latent heat''' of vaporisation]] of the [[water]] [[steam]] correct to two [[Significant Figures|significant figures]].
|-
| style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities in [[SI Unit]]s'''
E = 4.1J1kJ = 4.1x10<sup>3</sup>J
m = 15g = 15x10<sup>-3</sup>kg
<math>L_v = \frac{E}{m}</math>
<math>L_v = \frac{4.1\times 10^3}{15 \times 10^{-3}}</math>
<math>L_v = 2732.3 733 \times 10^5 J/kg</math>
<math>L_v \approx 270 2.7 \times 10^5 J/kg</math>
| style="height:20px; width:300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''