Answer:
The first is true
The second is true IF the statement means that the human body contains energy
The third is true
The fourth is false
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:
Kinetic energy=Ek
Ek=(1/2)mv²
Ek=480 J
v=8 m/s
mass=?
Ek=(1/2)mv²
480 J=(1/2)m(8 m/s)²
480 J=(32 m²/s²) m
m=(480 J)/(32 m²/s²)=15 kg
answer: the mass of the object is 15 kilograms.
