Answer:
Scientists must collect accurate information that allows them to make evolutionary connections among organisms. Similar to detective work, scientists must use evidence to uncover the facts. In the case of phylogeny, evolutionary investigations focus on two types of evidence: morphologic (form and function) and genetic.
Explanation:
This what I think
Answer:
The main difference between the heat of formation and heat of reaction is that heat of formation is the amount of energy either absorbed or released during the formation of a compound whereas heat of reaction is the amount of energy either absorbed or released during any chemical reaction.
Answer:
2
Explanation:
The 1 & 2 are both signifigant becuase they are presented in scientific notation.
Answer:
The pH of a solution is simply a measure of the concentration of hydrogen ions,
H
+
, which you'll often see referred to as hydronium cations,
H
3
O
+
.
More specifically, the pH of the solution is calculated using the negative log base
10
of the concentration of the hydronium cations.
∣
∣
∣
∣
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
a
a
pH
=
−
log
(
[
H
3
O
+
]
)
a
a
∣
∣
−−−−−−−−−−−−−−−−−−−−−−−−
Now, we use the negative log base
10
because the concentration of hydronium cations is usually significantly smaller than
1
.
As you know, every increase in the value of a log function corresponds to one order of magnitude.
Explanation:
Concrete is formed of sand. Is it incorrect to suggest that some houses are built using concrete blocks?