Answer:
3.40 g
Explanation: don't have one :P
Answer: The chemical equation for the formation one mole of
from its elements in their standard states is 
Explanation:
The standard enthalpy of formation or standard heat of formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its constituent elements, with all substances in their standard states.
The chemical equation for the formation one mole of
from its elements in their standard states is:

where (s) represents solid state and (g) represents gaseous state.
Scientists use a Graduated Cylinder