Answer: 3 moles Na
Explanation: To find the number of moles of Na, divide the number of atoms of Na with the Avogadro's Number.
1.806x10²⁴ atoms Na x 1 mole Na / 6.022x10²³ atoms Na
= 2.99 or 3 moles Na
Answer: Gravity.
Explanation:
Newton realized that the reason the planets orbit the Sun is related to why objects fall to Earth when we drop them. The Sun's gravity pulls on the planets, just as Earth's gravity pulls down anything that is not held up by some other force and keeps you and me on the ground.
Answer
is: <span>the
percent ionizationof formic acid is 1,82%.
Chemical reaction: HCOOH(aq) </span>⇄ H⁺(aq)
+ HCOO⁻(aq).<span>
pKa(</span>HCOOH) = 3,77.
Ka(HCOOH) = 1,7·10⁻⁴.
c(HCOOH) = 0,5 M.
<span>
[H</span>⁺]
= [HCOO⁻] = x; equilibrium
concentration.<span>
[HA] = 0,1 M - x.
Ka = [H</span>⁺] · [HCOO⁻] / [HCOOH].<span>
0,00017 = x² / 0,5 M - x.
Solve quadratic equation: x = 0,0091 M.
α = 0,0091 M ÷ 0,5 M · 100% = 1,82%.</span>