Answer:
1027.62 g
Explanation:
For
:-
Mass of
= 296.1 g
Molar mass of
= 27.66 g/mol
The formula for the calculation of moles is shown below:
Thus,

From the balanced reaction:-

1 mole of
react with 3 moles of oxygen
Thus,
10.705 mole of
react with 3*10.705 moles of oxygen
Moles of oxygen = 32.115 moles
Molar mass of oxygen gas = 31.998 g/mol
<u>Mass = Moles * Molar mass = 32.115 * 31.998 g = 1027.62 g</u>
Answer: 1.997 M
Explanation:
molarity = moles of solute/liters of solution or 
first we have to find our moles of solute (mol), which you can find by dividing the mass of solute by molar mass of solute
mass of solute: 92 g
molar mass of solute: 46.08 g/mol
let's plug it in:

next, we plug it into our original equation:

Answer:
pKa = 3.675
Explanation:
∴ <em>C</em> X-281 = 0.079 M
∴ pH = 2.40
let X-281 a weak acid ( HA ):
∴ HA ↔ H+ + A-
⇒ Ka = [H+] * [A-] / [HA]
mass balance:
⇒<em> C</em> HA = 0.079 M = [HA] + [A-]
⇒ [HA] = 0.079 - [A-]
charge balance:
⇒ [H+] = [A-] + [OH-]... [OH-] is negligible; it comes from to water
⇒ [H+] = [A-]
∴ pH = - log [H+] = 2.40
⇒ [H+] = 3.981 E-3 M
replacing in Ka:
⇒ Ka = [H+]² / ( 0.079 - [H+] )
⇒ Ka = ( 3.981 E-3 )² / ( 0.079 - 3.981 E-3 )
⇒ Ka = 2.113 E-4
⇒ pKa = - Log ( 2.113 E-4 )
⇒ pKa = 3.675
Answer:
b. 6.02 x 1023 molecules
Explanation:
The formula mass of ammonia is 14 + 1 × 3 = 17.
The number of moles in 27.6g ammonia is 27.6 ÷ 17 = 1.62 mol.
A mole is 6.02 × 10²³, so the number of hydrogen atoms in a 1.62 moles of ammonia is 1.62 × 6.02 × 10²³ × 3 = 2.93 × 10² atoms.