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Can somebody please help me with these questions & showing my work?Question 1

Can somebody please help me with these questions & showing my work?Question 1-example-1
User DavidVdd
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1 Answer

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20 votes

ANSWER

250 kJ

Step-by-step explanation

The given amount of lead is at its melting point. Every change of phase is produced at a constant temperature, so to find how much heat is needed to melt this lead, we only need the latent heat of fusion,


Q=m\cdot L_f

The mass m = 10kg and Lf = 0.25x10⁵ J/kg,


Q=10\operatorname{kg}\cdot0.25*10^5J/kg=250,000J=250kJ

Hence, the amount of heat needed to melt 10kg of lead at its melting point is 250 kJ

User Mariane
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