What question? Lhh this is hilarious.
The solution for this problem is:
Let x denote the specific rotation, R; andLet y denote the specific rotation, S = -x
Solution:60 x - 40 x/100 = - 43
20x = - 4300Divide both sides by 20The answer is:x = - 215 is the specific rotation of the pure r isomer.
Answer:
Notice that the number of atoms of
K
and
Cl
are the same on both sides, but the numbers of
O
atoms are not. There are 3
O
atoms on the the left side and 2 on the right. 3 and 2 are factors of 6, so add coefficients so that there are 6
O
atoms on both sides.
2KClO
3
(
s
)
+ heat
→
KCl(s)
+
3O
2
(
g
)
Now the
K
and
Cl
atoms are not balanced. There are 2 of each on the left and 1 of each on the right. Add a coefficient of 2 in front of
KCl
.
2KClO
3
(
s
)
+ heat
→
2KCl(s)
+
3O
2
(
g
)
The equation is now balanced with 2
K
atoms,
Answer:
pH = 2.69
Explanation:
The complete question is:<em> An analytical chemist is titrating 182.2 mL of a 1.200 M solution of nitrous acid (HNO2) with a solution of 0.8400 M KOH. The pKa of nitrous acid is 3.35. Calculate the pH of the acid solution after the chemist has added 46.44 mL of the KOH solution to it.</em>
<em />
The reaction of HNO₂ with KOH is:
HNO₂ + KOH → NO₂⁻ + H₂O + K⁺
Moles of HNO₂ and KOH that react are:
HNO₂ = 0.1822L × (1.200mol / L) = <em>0.21864 moles HNO₂</em>
KOH = 0.04644L × (0.8400mol / L) = <em>0.0390 moles KOH</em>
That means after the reaction, moles of HNO₂ and NO₂⁻ after the reaction are:
NO₂⁻ = 0.03900 moles KOH = moles NO₂⁻
HNO₂ = 0.21864 moles HNO₂ - 0.03900 moles = 0.17964 moles HNO₂
It is possible to find the pH of this buffer (<em>Mixture of a weak acid, HNO₂ with the conjugate base, NO₂⁻), </em>using H-H equation for this system:
pH = pKa + log₁₀ [NO₂⁻] / [HNO₂]
pH = 3.35 + log₁₀ [0.03900mol] / [0.17964mol]
<h3>pH = 2.69</h3>
Compounds are elements and its a pure substance with a gised composition.
Mixtures two or more subtances mixed to together.There are 2 type of mixtures.
Homegenous Mixtures (Solutions)-Two or more substances mixed but is uniform, you cant see the different mixtures.
Ex:Sugar mixed with water.The sugar dissolves and becomes one with the water.
Heterogeneous Mixtures-Two or more substances mixed but is not uniformed.You can see all the substances put into the mixture.
Ex:A salad, you can see whats all mixed in the sald and can pick it apart.
