4. Material.

Question 0

5. What is tallow?

Answer 0

animal fat, the rendered fat of cattle and sheep; white and almost tasteless when pure.
Harder than grease, composed of glycerides of fatty acids, containing a large proportion of palmitic acid and steric acid. It is used to make candles, soap and glycerol margarine.

Question 1

1. What is nidle valve?

Answer 1

It permits excess air to be released from the expansion tank prior to heat-up of the system.

Question 2

6. What is Potassium Hydroxide?

Answer 2

A brittle white deliquescent solid KOH that dissolves with much heat in less than its weight of water to form a strong alkaline and caustic solution, also called Caustic Potash.