This would mean the masses of Na and Cl are 22.99g and 35.45g respectively. Therefore, the percent composition of NaCl is 39.3% sodium and 60.7% chloride.
Answer:
you can identify the properties of an element by studying its_____ on the ... between metals and nonmetals on the periodic table are the _____ which have ...
Explanation:
The moles are the estimation of the quantities like the molecules and the atoms. There are 7.984 moles of aluminum present in the 2.154 × 10⁻¹ kg substance. Thus, option b is correct.
<h3>What are moles?</h3>
The moles give the estimation of the smaller entities by the ratio of mass or weight to the molar mass of the substance.
The formula for moles is given as,
Moles = mass ÷ molar mass
Given,
Mass of aluminium = 2.154 × 10⁻¹ kg = 2.154 × 10² gm
Molar mass of Al = 26.9 g/mol
Substituting values above:
Moles = 2.154 × 10² gm ÷ 26.9 g/ mol
= 7.984 mol
Therefore, option. 7.984 moles of aluminum are present.
Learn more about moles here:
brainly.com/question/15209553
#SPJ4
Answer:
Kc = 9.52.
Explanation:
<em>A + 2B ⇌ C,</em>
Kc = [C]/[A][B]²,
Concentration: [A] [B] [C]
At start: 0.3 M 1.05 M 0.55 M
At equilibrium: 0.3 - x 1.05 - 2x 0.55 + x
0.14 M 1.05 - 2x 0.71 M
- For the concentration of [A]:
∵ 0.3 M - x = 0.14 M.
∴ x = 0.3 M - 0.14 M = 0.16 M.
∴ [B] at equilibrium = 1.05 - 2x = 1.05 M -2(0.16) = 0.73 M.
<em>∵ Kc = [C]/[A][B]²</em>
∴ Kc = (0.71)/(0.14)(0.73)² = 9.5166 ≅ 9.52.
Answer:
Here
Explanation:
Some assume our planet's changing distance from the sun causes the change in the seasons. That's logical, but not the case for Earth. Instead, Earth has seasons because our planet's axis of rotation is tilted at an angle of 23.5 degrees relative to our orbital plane, that is, the plane of Earth's orbit around the sun