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<span>Carbonic acid is referred to as volatile acid because it is produced from a gas that evaporates quickly.
Volatility is the likeliness of a substance to vaporize. That is the tendency of the substance to pass to the gaseous phase. That means that these substances have a high vapor pressure. Coming from a gas, Carbonic Acid has a high tendency to pass to the vapor phase.
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Milk mixture and heterogeneous
Answer:

Explanation:
Given :
Mass of a bar of lead = 115.2 g
Initial water level
= 25 mL
Final water level
= 35.5 mL
Difference in the water level = 35.5 - 25
= 10.5 mL
= 
We know that when a body is submerged in water, it displaces its own volume of water.
Therefore, the volume of the lead bar = volume of the water displaced = 10.5 mL = 
We know that mathematically, density is the ratio of mass of body to its volume.
Density of the lead bar is given by :


= 
The molecular formula tell us what elements the atoms are, and how many moles and atoms are attributed toward each element.
The molecular model tells us how the atoms/elements are bonded together.
Molecular formula : CH4
H
l
Molecular model: H -- C -- H
l
<span> H</span>
THE ANSWER IS B. The reducing of oxidation state (-1 to -2, a change of -1, a REDUCTION) is what makes it a reduction.