[cfd]

I would be very grateful if someone would be able to help me understand what compound is used here to create heat.

Back story: I like to take stuff apart to see how things works and after recently using a Raid Fumigator I decided to cut one open to view the inter workings.

I am trying to identify these white pebbles. From what i can see the can works in this following matter-
White pebbles sit at bottom of a perforated can. This can is then dropped into plastic cup that holds few spoons of water. Water then enters the can through perforated holes and reacts with white pebbles. This reaction causes heat which in turn heats up the pot that holds fumigation chemical.

Im including a link to a product and photos below. I would be extremely grateful if someone would help me identify these white pebbles and why they create heat after being exposed to water.

Thanks in advance!
cfd

http://www.raidkillsbugs.com/en-us/products/raid-fumigator-fumigating-fogger

[ATMyller]

Basic exothermic reaction between water and alkali oxide or metal. Most likely either calcium oxide where reaction CaO+ H2O → Ca(OH)₂ creates heat or magnesium with reaction Mg + 2H₂O → Mg(OH)₂ + H₂.

[cfd]

Basic exothermic reaction between water and alkali oxide or metal. Most likely either calcium oxide where reaction CaO+ H2O → Ca(OH)₂ creates heat or magnesium with reaction Mg + 2H₂O → Mg(OH)₂ + H₂.

Appreciate your quick response, looks like it is quicklime.

Thanks again!
cfd