Enthalpy problem 3?

Question

You are at your cabin in the woods. Will you be able to take a hot bath tonight if only .1lb of propane remains in the tank?Explain,

WILL RATE YOU 10 POINTS

Answer 1

Propane energy content varies considerably, but 21,400 BTU/lb is a reasonable estimate. If you have 0.1 lb, then 2100 BTU of energy. Neglecting losses, water specific heat is 1 BTU/lbm°F. Assuming 60°F water going to 100°F temp required, you can heat 53 lb of water, or 6 1/2 gallons.

Really too little for a hot bath, maybe OK for a very short shower.

Answer 2

How many btu's in .1 lb of propane? How many cu ft. of water in tub? specific heat of water times cu ft water is total btu's needed to heat to bath temp. If btu's needed to heat amt. of water exceeds total propane btu's available, then no. If btu's of propane exceeds btu's to heat h2o then yes.

Insufficient info if quantity of water not provided.