Answer:
54.1 % Ca, 43.2 % O, 2.7% H
Explanation:
Molecular formula for calcium hydroxide is Ca(OH)₂
As we don't have a mass of Ca(OH)₂ to find out the percentage composition, we consider that the question refers to 1 mol of compound.
1 mol of hydroxide weighs 74.08 g
1 mol of hydroxide has 1 mol of Ca, therefore 40.08 g are Ca
2 moles of O therefore 32g are O
2 moles of H therefore 2 g are H
Percentage composition is known as (Mass of element/Total mass) . 100
- (40.08 / 74.08) . 100 = 54.1 %
- (32 / 74.08) . 100 = 43.2 %
- (2 / 74.08) . 100 = 2.7%
The acronym 'DNA' stands for deoxyribonucleic acid.
DNA is used to 'code' the genetic makeup of all living organisms, and is found inside the nucleus of the cell(Eukaryotes) or just floating in the cytoplasm of the cell(Prokaryotes). DNA is made up of 4 different pairs of base molecules(nucleotides) that are slightly different from another. The similar molecule structure RNA(ribonucleic acid) differs from DNA in that RNA nucleotides are just slightly different from the nucleotides of DNA. This difference is that RNA nucleotides have a hydroxide group(OH) where the DNA nucleotides just have a hydrogen atom.
Because the DNA nucleotide doesn't have the hydroxide group it has one less oxygen than RNA nucleotides do. This is where DNA derives the prefix "deoxy-," meaning "without oxygen."
The prefix "ribo-" is given to molecules with a certain configuration of a set of 3 consecutive but not necessarily contiguous CHOH(asymmetric) groups.
The combined form "nucleo-" is used to imply something that has to do with the nucleus, such as the nucleus of a cell where DNA is stored in Eukaryotes.
And finally, the ending of the acronym: "acid." DNA is an acid because the 4 nucleotides each contain a phosphate group, which are acidic.
And thus, we get our answer: deoxyribonucleic acid, and the meaning:
deoxy-ribo-nucleic acid
(without oxygen) + (has 3 CHOH groups) + (in/of the nucleus) + (acidic)
Thus, DNA is a molecule is basically an acidic molecule residing in the nucleus with 3 CHOH groups and is missing oxygen atoms.
I know this isn't really what you're looking for, but honestly I had a great time doing a little research into the name!
Hope this explains it a little! c;
Answer:
c. 7.14
Explanation:
The buffer solution is formed by a weak acid ( hypochlorous acid, HClO) and its conjugate base (hypochlorite ClO⁻, coming from sodium hypochlorite NaClO). We can calculate the pH using the Henderson-Hasselbach equation.
pH = pKa + log [base]/[acid]
pH = -log 3.8 × 10⁻⁸ + log 0.111/0.211
pH = 7.14
Answer:
31.58 L
Explanation:
From the question given above, the following data were obtained:
Initial mole (n₁) of gas = 1.90 moles
Initial volume (V₁) = 40 L
Final mole (n₂) = 1.90 – 0.40 = 1.5 moles
Final volume (V₂) =.?
The final volume of the gas can be obtained as follow;
V₁ / n₁ = V₂ / n₂
40 / 1.9 = V₂ / 1.5
Cross multiply
1.9 × V₂ = 40 × 1.5
1.9 × V₂ = 60
Divide both side by 1.9
V₂ = 60 / 1.9
V₂ = 31.58 L
Thus, the final volume of the gas is 31.58 L
