Answer:
BaO
Explanation:
The barium oxide chemical formula is BaO. The molar mass is 153.33 g/mol. The molecule is formed by one barium cation Ba2+ and one oxide anion O2-. Both ions are bound by one ionic bond.
Answer:
C Accelerometer
Explanation:
An accelerometer is an electromechanical device used to measure acceleration forces. Such forces may be static, like the continuous force of gravity or, as is the case with many mobile devices, dynamic to sense movement or vibrations. Acceleration is the measurement of the change in velocity, or speed divided by time.
Hpoe this Helps!
3.44x10^2
you move the decimal over to get a single digit number with change. The number of times you move the decimal is the number for the 10 power
<span>pharmacokinetics
This question is simply a matter of knowing the definition of terms being used in your class. So let's look at the 4 options and see what makes sense.
spectrometry
* This is the determination of elements based upon the light spectrum associated with the elements. It can be either an emission spectrum you get by energizing the substance under test, or an absorption spectrum to see what wavelengths the substance absorbs. But in either case, this doesn't make sense in the statement, so it's a wrong answer.
LD50
* This terms means "Lethal Dose 50%" which is the amount of the substance needed such that half of the creatures that receive that dose die. In the context of the statement, this doesn't make sense, so it's a wrong answer.
pharmacokinetics
* This is the study of how drugs move through the body and are metabolized. This sounds like something that makes sense for the statement in the question, so it's most likely the correct answer. Let's see what the next choice is.
chromatography
* This is a laboratory method of separating substances using differential rates of diffusion. This doesn't make sense given the statement in the question, so it's a wrong choice.
So of the 4 available choices, 3 of them do not make sense given the statement in question and the only one that does make sense is "pharmacokinetics"</span>
The idea here is that you need to figure out how many moles of magnesium chloride,
MgCl
2
, you need to have in the target solution, then use this value to determine what volume of the stock solution would contain this many moles.
As you know, molarity is defined as the number of moles of solute, which in your case is magnesium chloride, divided by liters of solution.
c
=
n
V
So, how many moles of magnesium chloride must be present in the target solution?
c
=
n
V
⇒
n
=
c
⋅
V
n
=
0.158 M
⋅
250.0
⋅
10
−
3
L
=
0.0395 moles MgCl
2
Now determine what volume of the target solution would contain this many moles of magnesium chloride
c
=
n
V
⇒
V
=
n
c
V
=
0.0395
moles
3.15
moles
L
=
0.01254 L
Rounded to three sig figs and expressed in mililiters, the volume will be
V
=
12.5 mL
So, to prepare your target solution, use a
12.5-mL
sample of the stock solution and add enough water to make the volume of the total solution equal to
250.0 mL
.
This is equivalent to diluting the
12.5-mL
sample of the stock solution by a dilution factor of
20
.
