Answer:
Subbituminous coal can form at temperatures as low as 35 to 80 °C (95 to 176 °F) while anthracite requires a temperature of at least 180 to 245 °C (356 to 473 °F).
Sub-types: Cannel coal
Child material class: Lignite
Explanation:
Mercury bc it is melting and getting closer
Answer:
All carbons in the carbon skeleton contain the maximum number of hydrogen atoms
Explanation:
Saturated fats are class of compounds having all the fatty acids containing only single bonds. In other words, carbon skeleton has only single bonds.
Unsaturated compounds undergoes hydrogenation to form saturated fats.
In hydrogenation, hydrogen atoms are added to the carbon attached to double bond. After become saturated, no more hydrogen atoms can be added.
Therefore, it can be said that in saturated fats all carbons in the carbon skeleton contain the maximum number of hydrogen atoms.
Solution :
For the reaction :

we have
![$Ka = \frac{[\text{Tris}^- \times H_3O]}{\text{Tris}^+}$](https://tex.z-dn.net/?f=%24Ka%20%3D%20%5Cfrac%7B%5B%5Ctext%7BTris%7D%5E-%20%5Ctimes%20H_3O%5D%7D%7B%5Ctext%7BTris%7D%5E%2B%7D%24)


Clearing
, we have 
So to reach
, one must have the
concentration of the :
![$\text{[OH}^-]=10^{-pOH} = 6.31 \times 10^{-7} \text{ moles of base}$](https://tex.z-dn.net/?f=%24%5Ctext%7B%5BOH%7D%5E-%5D%3D10%5E%7B-pOH%7D%20%3D%206.31%20%5Ctimes%2010%5E%7B-7%7D%20%5Ctext%7B%20moles%20of%20base%7D%24)
So we can add enough of 1 M NaOH in order to neutralize the acid that is calculated above and also adding the calculated base.


Volume NaOH 
Tris mass 
Now to prepare the said solution we must mix:
gauge to 1000 mL with water.
Answer:
c. contraction
Explanation:
Heating will cause substances to expand, or change their state (like solid to liquid) or it may be a chemical reaction.