How much corn syrup should be added to water to make 200 mL of a 10% by volume solution

The pKa of the α‑carboxyl group of serine is 2.21 , and the pKa of its α‑amino group is 9.15 . Calculate the average net charge

sleet_krkn [62]

Answer:

Net charge in serine at pH equal to 8.30 is "0"

Explanation:

At pH > $pK_{a}$ , carboxyl group exists as $-CO_{2}^{-}$ (charged)

At pH < $pK_{a}$ , carboxyl group exists as -COOH (neutral)
At pH > $pK_{a}$ , amino group exists as $-NH_{2}$ (neutral)
At pH < $pK_{a}$ , amino group exists as $-NH_{3}^{+}$ (charged)
So, at pH = 8.30, both carboxyl and amino group exists in charged state.
Net charge in serine at pH equal to 8.30 is "0".
Structure of serine at pH equal to 8.30 has been shown below.

8 0

3 years ago

A sealed can of your favorite soda has a carbon dioxide gas (C0) volume of 0.05 L. When it is refrigerated, the

liubo4ka [24]

Answer:

Explanation:

The new pressure can be found by using the formula for Boyle's law which is

$P_1V_1 = P_2V_2$

Since we are finding the new volume

$V_2 = \frac{P_1V_1}{P_2} \\$

From the question we have

$V_2 = \frac{207000 \times 0.05}{101000} = \frac{10350}{101000} \\ = 0.102475...$

We have the final answer as

Hope this helps you

8 0

3 years ago

Amino acids are the building blocks of proteins. The simplest amino acid is glycine . Draw a Lewis structure for glycine. (Hint:

madam [21]

Answer:

Sorry for the lack of precision, if you have any questions you can consult me again.

Explanation:

Glycine is an amino acid, forms proteins and is also called in its molecular chemical formula as C2H5NO2

5 0

2 years ago

A solution of CaCl 2 in water forms a mixture that is 42.0 % calcium chloride by mass. If the total mass of the mixture is 839.6

Lerok [7]

Answer : The masses of calcium chloride and water used were, 352.6 g and 487.0 g.

Explanation :

As we are given that 42.0 % calcium chloride by mass that means 42.0 grams of calcium chloride present in 100 grams of solution.

In the solution or mixture, 42.0 % calcium chloride and 58.0 % (100-42.0=58.0) water.

Now we have to determine the mass of calcium chloride for 839.6 grams of solution.

As, 100 grams of solution contains 42.0 grams of calcium chloride

So, 839.6 grams of solution contains $\frac{42.0}{100}\times 839.6=352.6$ grams of calcium chloride

Thus, the mass of calcium chloride used is, 352.6 grams.

Now we have to determine the mass of water.

Mass of water = Mass of solution - Mass of calcium chloride

Mass of water = 839.6 g - 352.6 g

Mass of water = 487.0 g

Thus, the mass of water used is, 487.0 grams.

6 0

3 years ago

Determine the pH of the resulting solution if 25 mL of 0.400 M strychnine (C21H22N2O2) is added to 50 mL of 0.200 M HCl? Assume

DIA [1.3K]

Answer:

pH = 4.56

Explanation:

The strychnine reacts with HCl as follows:

C₂₁H₂₂N₂O₂ + HCl ⇄ C₂₁H₂₂N₂O₂H⁺ + Cl⁻

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For strychnine buffer:

pOH = 5.74 + log [C₂₁H₂₂N₂O₂H⁺] / [C₂₁H₂₂N₂O₂]

Initial moles of C₂₁H₂₂N₂O₂ are:

0.025L * (0.400 mol / L) = 0.01 moles C₂₁H₂₂N₂O₂

And of HCl are:

0.05L * (0.200 mol / L) = 0.01 moles HCl

That means after the reaction, you will have just 0.01 moles of C₂₁H₂₂N₂O₂H⁺ in 50mL + 25mL = 0.075L. And molarity is:

[C₂₁H₂₂N₂O₂H⁺] = 0.01 mol / 0.075L = 0.1333M

This conjugate acid, is in equilibrium with water as follows:

C₂₁H₂₂N₂O₂H⁺(aq) + H₂O(l) ⇄ C₂₁H₂₂N₂O₂ + H₃O⁺

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<em>Where Ka = Kw / Kb = 1x10⁻¹⁴ / 1.8x10⁻⁶ = 5.556x10⁻⁹</em>

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Ka is defined as:

Ka = 5.556x10⁻⁹ = [C₂₁H₂₂N₂O₂] [H₃O⁺] / [C₂₁H₂₂N₂O₂H⁺]

In equilibrium, concentrations are:

C₂₁H₂₂N₂O₂ = X

H₃O⁺ = X

C₂₁H₂₂N₂O₂H⁺ = 0.1333M - X

Replacing in Ka expression:

5.556x10⁻⁹ = [X] [X] / [0.1333M - X]

7.39x10⁻¹⁰ - 5.556x10⁻⁹X = X²

7.39x10⁻¹⁰ - 5.556x10⁻⁹X - X² = 0

Solving for X:

X = - 2.72x10⁻⁵M → False solution. There is no negative concentrations

X = 2.72x10⁻⁵M → Right solution.

As H₃O⁺ = X

H₃O⁺ = 2.72x10⁻⁵M

And pH = -log H₃O⁺

4 0

3 years ago

How much corn syrup should be added to water to make 200 mL of a 10% by volume solution​

How much corn syrup should be added to water to make 200 mL of a 10% by volume solution