Answer:
An open system
Explanation:
An open system is a system in which both matter and energy are exchanged freely between the system and the surroundings.
An example is a pot of water boiling on the stove. The surroundings (the stove) can supply heat energy to the water and the water can escape into the atmosphere.
A <em>closed system</em> is a system in which energy but not matter is exchanged freely between the system and the surroundings.
An example is a pressure cooker on the stove. The surroundings (the stove) can supply heat energy to the food inside, but no matter can escape through the closed lid.
An <em>isolated system</em> is a system in which neither energy nor matter can be exchanged between the system and the surroundings.
An example is a thermos of hot soup. The cap prevents matter from escaping and the shiny interior reflects heat back into the soup.
Answer:
Due to presence of a triple bond between the two N−atoms, the bond dissociation enthalpy (941.4 kJ mol
−1
) is very high. Hence, N
2
is the least reactive.
Answer:
Density independent factor
Explanation:
in dense areas where people livein very close and tight spaces
Explanation:
The chemical formula of an ionic compound can be written by using the symbols of the respective cations and anions.
The overall charge on the molecule should be zero.
Hence, the total charge of cations=total charge of anions.
The symbols of the given molecules are shown below:
sodium chloride ---- NaCl
magnesium chloride ---
calcium oxide ---- CaO
lithium phosphide----
aluminum sulfide ----- 
calcium nitride---- 
