Question

1) Peter is heating water on the stove to boil eggs for a picnic. How much heat is required to raise the temperature of his 10.0-kg vat of water from 20.0℃ to 100.0℃?
Formula>> Q=mTcp

2)Under the spreading chestnut tree of the village blacksmith dunks red-hot horseshoe into a large bucket of 22.0℃ water. How much heat was lost by the horseshoe in vaporizing 0.0100 kg of water?
Formula>> 2.26x10^6J/kg

3)By January, the 3.0 kg of water in the birdbath in Robyn's backyard has frozen to a temperature of -7.0℃. As the season changes, how much heat must be added to a water to make it a comfortable 25℃ for the birds?
formula>> Q=mTcp

Please help me!! :)
Thank you soooo much!! :D

Answer 1

sorry,it's 'physics heat'.. please help me.

Answer 2

1)
Q=c•m•ΔT=4183•10•(100-20)=3346400 J
2)
Q=Lm = 2260000•0.01 = 22600 J
3)
Q= Q₁+Q₂+Q₃= c₁•m•ΔT₁+rm+ c₂•m•ΔT₂=
=2060•3•7+ 335000•3+4183•3•25 =
=43260 + 1005000+313725 =1361985 J