Answer:
1.68 × 10²³ Molecules
Explanation:
As we know that 1 mole of any substance contains exactly 6.022 × 10²³ particles which is also called as Avogadro's Number. So in order to calculate the number of particles (molecules) contained by 0.280 moles of Br₂, we will use following relation,
Moles = Number of Molecules ÷ 6.022 × 10²³ Molecules.mol⁻¹
Solving for Number of Molecules,
Number of Molecules = Moles × 6.022 × 10²³ Molecules.mol⁻¹
Putting values,
Number of Molecules = 0.280 mol × 6.022 × 10²³ Molecules.mol⁻¹
Number of Molecules = 1.68 × 10²³ Molecules
Hence,
There are 1.68 × 10²³ Molecules present in 0.280 moles of Br₂.
Explanation:
Oxidation state of Nitrogen in N2O5 is +5
Answer:
a. Phosphoric Acid
b. Acetic Acid
c. Hypochlorous Acid
Explanation:
A buffer works when the pH of this one is in pKa ± 1. That means, to find which buffer system works in some pH you need to find pKa:
pKa = -log Ka
<em>pKa Acetic acid:</em>
-log1.8x10⁻⁵ = 4.74
<em>pKa phosphoric acid:</em>
-log7.5x10⁻³ = 2.12
<em>pKa hypochlorous acid:</em>
-log3.5x10⁻⁸ = 7.46
a. For a pH of 2.8 the best choice is phophoric acid because its effective range is: 1.12 - 3.12 and 2.8 is between these values.
b. pH 4.5. Acetic acid. effective between pH's 3.74 - 5.74
c. pH 7.5. Hypochlorous acid that works between 6.46 and 8.46
Answer:
Carbon - 13
Explanation:
For most of the elements other than that of hydrogen, the isotopes are named for the mass number.
Example : Carbon atoms with 6 neutrons have mass number of 12 ( as 
), so they are known as carbon-12.
Given that:
Protons = 6
Neutrons = 7
Mass = 6 + 7 = 13
So the name is Carbon - 13 . The symbol is 
Yes you can it will not just have 5 :)
