Question

You draw a 35l bath of water but at 47°C too hot ,so we start adding

9.0degree censius how much
Cold water you need
to add to bring
the bath water to a
Comfortable: 39°C degree censius

Answer 1

Answer:9.33 L

Step-by-step explanation:

If no energy is lost then heat lost by the hot water= heat gained by the cold.

This means Qhot+Qcold=0

Q (heat) = m(mass) c(specific heat) *change in temperature

m= Density* Volume

change in temp for the hot = 39-47= -8

change in temp for the cold = 39- 9= 30

this will give us

0 = (Density *35 L) ( c) (-8)+ (Density *(Volume of cold water))*(c)*(30)

we can divide everything by density and specific heat to get

0=-280+ (Volume cold)(30)

Volume cold = 280/30=9.33 L