As [USER=10952]@blr_p[/USER] suggested, it will have to be a metal pipe with flexible rubber hoses at both ends so that the cylinder in the store room or gas in the kitchen can be moved about.
It is better to have valves at both metal end points in the kitchen and the the store room so that you have an easy way to shutoff the gas supply in the kitchen itself when you are servicing / replacing.
The distance looks more than 8 ft from the map. 10ft in the kitchen + around 11 ft. in the store room + 2x8 ft. in the foyer. looks close to 40ft. Don't think PVC pipes would be suitable for gas.
Similar to water pipes, gas pipes have to have airtight connections sealed properly to prevent leakage.
Remember more the number of interconnections/elbow joints/valves etc. more the number of places that the gas can leak. Also at night we close the valve on the cylinder before going to sleep for safety purposes. If the cylinder is in a different room you will have to remember to shutoff the valve from that room. Also please do not conceal the pipes as finding any leaks would become very difficult.
My suggestion would be to catch hold of the HP/BP guy who comes to service the gas at home, give him some chai pani and ask him about this. This setup is similar to the one the restaurant/hotel kitchens have where the cylinders are kept outside for ease of access for replacing them when empty and he would be familiar with it.
Get this done from a professional.
