You are building a machine to process dates into tasty cookies at a factory. This machine cannot corrode into your date paste, or the taste of the cookies will be ruined. Dates have a natural pH of 6.2 to 6.4. Which conjugate base would you choose to make a buffer solution to test materials for your machine to make sure that they will not ruin the flavor of the cookies

Acid Ka Hydrochloric HCI Acetic CH3COOH 1.8 x 10 Carbonic H2CC 4.3 x 10 Dihydrogen phosphate H-PO, 6.2 x 10 Boric Acid HaBO5.4x 10 T0

a) CI
b) CH3COO
c) HCO3
d) HPO
e) H2BOs

C) HCO₃⁻

Explanation:

pKa of a buffer is defined as -log Ka of the buffer:

For:

Acetic acid: -log 1.8x10⁻⁵ = 4.74

Carbonic acid: -log 4.3x10⁻⁷ = 6.37

Dihydrogen phosphate: -log 6.2x10⁻⁸ = 7.21

Boric Acid: -log 5.4x10⁻¹⁰ = 9.27

The maximum buffering capacity is when pH is ± 1 pKa.

As Carbonic acid has the nearest pKa to desire pH, you must choose HCO₃⁻ as conjugate base.

C) HCO₃⁻

your answer would be “dry”

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.