The liquids hexane
and water are placed in a test tube. The test tube is stoppered, shaken, and
placed in a test tube rack. The liquids separate into two distinct
layers because hexane and water have different molecular polarities. The answer
is number 2.
Answer:
Explanation:
Your strategy here will be to
use the chemical formula of carbon dioxide to find the number of molecules of
CO
2
that would contain that many atoms of oxygen
use Avogadro's constant to convert the number of molecules to moles of carbon dioxide
use the molar mass of carbon dioxide to convert the moles to grams
So, you know that one molecule of carbon dioxide contains
one atom of carbon,
1
×
C
two atoms of oxygen,
2
×
O
This means that the given number of atoms of oxygen would correspond to
4.8
⋅
10
22
atoms O
⋅
1 molecule CO
2
2
atoms O
=
2.4
⋅
10
22
molecules CO
2
Now, one mole of any molecular substance contains exactly
6.022
⋅
10
22
molecules of that substance -- this is known as Avogadro's constant.
In your case, the sample of carbon dioxide molecules contains
2.4
⋅
10
22
molecules CO
2
⋅
1 mole CO
2
6.022
⋅
10
23
molecules CO
2
=
0.03985 moles CO
2
Finally, carbon dioxide has a molar mass of
44.01 g mol
−
1
, which means that your sample will have a mass of
0.03985
moles CO
2
⋅
44.01 g
1
mole CO
2
=
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
∣
∣
a
a
1.8 g
a
a
∣
∣
−−−−−−−−−
The answer is rounded to two sig figs, the number of sig figs you have for the number of atoms of oxygen present in the sample.
Answer:
The hydroxyl group
Explanation:
The molecular formulas of the above alcohols are
CH₃CH₂-OH
CH₃CH₂CH₂CH₂CH₂CH₂CH₂CH₂-OH
CH₃-OH
CH₃CH(CH₃)CH₂CH₂-OH
The functional group that is characteristic of all alcohols is the hydroxyl group (-OH).
Answer:
1) 17.5 mL
Explanation:
Hello,
In this case, the reaction between sulfuric acid and potassium hydroxide is:
In such a way, we notice a 1:2 molar ratio between the acid and the base, therefore, at the equivalence point we have:
And in terms of concentrations and volumes:
Thus, we solve for the volume of acid:
Best regards.
