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This is true, think of silver, gold, etc— those are heated to make them liquid
Explanation:
total heat = Heat required to convert 2 kg of ice to 2 kg of water at 0 °C + Heat required to convert 2 kg of water at 0 °C to 2 kg of water at 20 °C.
Heat=mhfg+mCpΔT
Here, m ( mass of ice) = 2 kg
hfg (latent heat of fusion of ice) = 334 KJ
Cp of water (specific heat) = 4.187 KJ/Kg-K
ΔT(Temperature difference) = 20 °C
Therefore, Heat required = 2 x 334 + 2 x 4.187 x (20 - 0 )
Heat reqd= 835.48 KJ
Therefore, to melt 2 kg of ice 835.48 KJ of heat is required.
Answer:
3m/s
Explanation:
Data obtained from the question include:
Initial speed (s1) = 4 m/s
Final speed (S2) = 7m/s
Change in speed (ΔS)
ΔS = s2 — s1
ΔS = 7 — 4
ΔS = 3m/s
Therefore, the change in speed is 3m/s
Answer:
if the heat of reaction is positive, the reaction is said to be endothermic; if negative, exothermic.
Explanation:
hope this helps
i am so sorry if this is the wrong answer
