It is O with a little 2 subscript. it represents two atoms of oxygen.
Electronegativity.
Electronegativity can be defined as the measure of affinity of the element towards electrons . Higher the affinity towards electrons higher the electronegativity.
Eg : Fluorine has a high electronegativity. This is because it has 7 valence electrons, to gain a noble gas configuration / complete outer shell it needs to gain one electron. Hence the positive nuclear charge of the nucleus will attract an electron so it can become a complete outer shell , therefore F is very reactive.
Higher the attraction of the nucleus to electrons , higher its affinity therefore higher electronegativity.
Answer:
Explanation:
<em>Endothermi</em>c processes absorb energy. The final state contains more energy than the initial state.
Since ice absorbs heat energy <em>in the process of completely melting</em> this is an <em>endothermic</em> process.
The process involves two stages: 1) heating the ice up to the melting point, which is 0ºC, and 2) melting the ice.
1. Heating the ice from -15ºC to 0ºC
a) Formula: Q = m×C×ΔT
- C = 2.108 kJ/kg.ºC (specific heat of ice)
b) Calculations:
- Q = m×C×ΔT = 1.6 kg × 2.108 kJ/kg.ºC × 15ºC = 50.592 kJ
2. Melting the ice at 0ºC
a) Formula: L = m × ΔHf
- ΔHf = 334 kJ/kg (latent heat of fussion)
b) Calculations
- L = m × ΔHf = 1.6 kg × 334 kJ/kg = 534.40 kJ
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<u>2. Total heat</u>
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- 50.592 kJ + 534.40 kJ = 584.992 kJ ≈ 590 kJ (rounded to 2 significant figures)