Answer:
Carbon has an ability of catenation which other group IV elements lack.
Explanation:
Catenation is the ability for an element to form multiple bonds with other elements leading rise to long chains of compounds.
An example is organic compounds.

Most likely in a damp environment such as a swamp, rainforest, lake, or forest
Answer:
The first row fits in period 2
The second row fits in period 3
Explanation:
Elements arranged vertically in the periodic table in groups that share similar chemical properties.
Elements are also organized horizontally in rows or periods
The length of each period is determined by the number of electrons that can occupy the sublevels being filled in that period.
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.
Answer:
balanced;
unbalanced;
unbalanced;
balanced;
Explanation:
CaO + 3C → CaC2 + CO //all elements are balanced
Na + H2O → 2NaOH + H2 //Na is not balanced on the left
4Fe + O2 → 2Fe2O3 //O is not balanced on the left
2Mg + O2 → 2MgO //left is equal to right, balanced