HELP ME PLEASE I BEG YOU

If you have 120. mL of a 0.100 M TES buffer at pH 7.55 and you add 3.00 mL of 1.00 M HCl, what will be the new pH? (The pKa of T

Simora [160]

Answer:

The new pH after adding HCl is 7.07

Explanation:

The formula for calculating pH of a buffer is

pH = pKa + log([Conjugate base]/[Acid])

<u>Before adding HCl,</u>

7.55 = 7.55 + log([Conjugate base]/[Acid])

⇔ log([Conjugate base]/[Acid]) = 0

⇔ [Conjugate base] = [Acid] = 1/2 x 0.100 = 0.05 M

⇒ Mole of Conjugate base = Mole of Acid = 0.05 M x 0.12 mL = 0.006 mol

<u>After adding HCl (3.00 mL, 1.00 M)</u>

⇒ Mole of HCl = 0.003 x 1 = 0.003 mol)

New volume solution is 120 m L+ 3 mL = 123 mL

HCl is a strong acid, it will convert the conjugate base to acid form, or we can express

Mole of new Conjugate base = 0.006 - 0.003 = 0.003 mol

⇒ Concentration = 0.003/0.123 M

Mole of new Acid form = 0.006 + 0.003 = 0.009 mol

⇒ Concentration = 0.009/0.123 M

Use the formula

pH = pKa + log([Conjugate base]/[Acid])

= 7.55 + log(0.003 / 0.009) = 7.07

8 0

3 years ago

¿Que hace diferente ala química de la alquimia?

viva [34]

Answer:

La distinción entre la química teóricamente teórica y la química avanzada es la química teórica teórica que se basa en un espiritualista, potente que percibe visualmente la autenticidad, mientras que la química espera que la autenticidad sea fundamentalmente mundana. Eso engendra una tremenda distinción, y la química nunca se hubiera alejado excepcionalmente de la remota posibilidad de que se hubiera quedado con el trascendentalismo antediluviano.

Explanation:

8 0

3 years ago

How many codons are needed to specify 3 amino acids?

Nataliya [291]

There need be 9 amino acids, as each amino acid is composed of 3 codons.
Hope this helps!

5 0

4 years ago

What is the kinetic energy of a 5 kg object moving at 7 m/s?

valina [46]

Answer:

122.5 Joule, or 122.5 j

Explanation:

Given,

mass of the object (m) = 5 kg

velocity of the object (v) = 7 m/s

Kinetic energy = $\frac{1}{2}$ × m × v²

Applying the formula:

Kinetic energy = $\frac{1}{2}$ × 5 × 7²

⇒ $\frac{1}{2}$ × 5 × 7 × 7

⇒ $\frac{245}{2}$

⇒ 122.5 Joule, or 122.5 j

Kinetic energy is the energy that an object gains as the result of the motion. It also depends on the mass of the object and force with which the motion is applied. In the given question, the mass of the object is 5 kg and the force of the velocity by which it is moving is 7 m/s.

3 0

3 years ago

I have 5 questions that need help to answer 1) What are covalent bonds and how do they form ? 2) How do you know which elements

8_murik_8 [283]

Answer:

covalent bond- a chemical bond that is the sharing of electron pairs between atoms

5 0

3 years ago