I need help with that

WILL MARK BRAINLIEST:

Anastaziya [24]

Answer:

Alienus

Explanation:

6 0

2 years ago

What concentrations of acetic acid (pKa = 4.76) and acetate would be required to prepare a 0.15 M buffer solution at pH 5.0? Not

Leni [432]

Answer:

Acetic acid 0,055M and acetate 0,095M.

Explanation:

It is possible to prepare a 0,15M buffer of acetic acid/acetate at pH 5,0 using Henderson-Hasselblach formula, thus:

pH = pka + log₁₀ [A⁻]/[HA] -Where A⁻ is acetate ion and HA is acetic acid-

Replacing:

5,0 = 4,76 + log₁₀ [A⁻]/[HA]

1,7378 = [A⁻]/[HA] (1)

As concentration of buffer is 0,15M, it is possible to write:

[A⁻] + [HA] = 0,15M (2)

Replacing (1) in (2):

1,7378[HA] + [HA] = 0,15M

2,7378[HA] = 0,15M

[HA] = 0,055M

Thus, [A⁻] = 0,095M

That means you need acetic acid 0,055M and acetate 0,095M to obtain the buffer you need.

i hope it helps!

7 0

2 years ago

Catalysts increase reaction rates by lowering the activation energy of a reaction.

Setler [38]

The answer is true, catalysts increase rates by lowering the activation energy of a reaction. Catalysts lower the reaction energy and so the reaction occurs faster. Enzymes perform the role of biological catalysts. Most metabolic pathways of the body are controlled by enzymes. Enzymes by classification are proteins.

4 0

2 years ago

Read 2 more answers

Moles of phosphorous in 15-35-15 fertilizer in 10g

guapka [62]

The composition of a fertilizer is usually express in NPK number. NPK number is in terms of Percent by mass of the said element which are Nitrogen, Phosphorus and Potassium. A 15-35-15 fertilizer has 15% Nitrogen, 35% Phosphorous, and 15% Potassium by mass. If you have 10 g of this fertilizer, to get the number of moles of phosphorus, you multiply the mass by 35%, which is equal to 10*0.35 or 3.5 g phosphorus. Then you divide the calculated mass of phosphorous by its molar mass which is 30.97 g/mol. Therefore, you have 3.5/30.97 which is equal to 0.1130 mol Phosphorus. This is the amount of Phosphorus in moles in the fertilizer.

6 0

2 years ago

Which two substances are covalent compounds? * C6H12O6(s) and KI(s) C6H12O6(s) and HCl(g) KI(s) and NaCl(s) NaCl(s) and HCl(g)

Ray Of Light [21]

Answer: Option (b) is the correct answer.

Explanation:

A covalent compound is defined as the compound in which sharing of electrons take place between the combining atoms. Generally, when two or more non-metals chemically combine together the it will lead to the formation of a covalent compound.

For example, $C_{6}H_{12}O_{6}$ and HCl is also a covalent compound.

And, a compound in which transfer of electrons occur between the combining atoms is known as an ionic compound. Whenever, a metal chemically combines with a non-metal then it will always lead to the formation of an ionic compound.

For example, KI is an ionic compound.

Thus, we can conclude that $C_{6}H_{12}O_{6}$ and HCl are the two substances which are covalent compounds.

7 0

2 years ago