Answer:
There are 1.05 x 10²⁴ molecules in 48.6 g N₂
Explanation:
1 mol of N₂ has a mass of (14 g * 2) 28 g.
Then, 48.6 g of N₂ will be equal to (48.6 g *(1 mol/ 28 g)) 1.74 mol.
Since there are 6.022 x 10²³ molecules in 1 mol N₂, there will be
(1.74 mol *( 6.022 x 10²³ / 1 mol)) 1.05 x 10²⁴ molecules in 1.74 mol N₂ (or 48. 6 g N₂).
Answer is: a. Rubidium (Rb) is more reactive than strontium (Sr) because strontium atoms must lose more electrons.
The ionization energy (Ei) is the minimum amount of energy required to remove the valence electron, when element lose electrons, oxidation number of element grows (oxidation process).
Alkaline metals (group 1), in this example rubidium, have lowest ionizations energy and easy remove valence electrons (one electron), they are most reactive metals.
Earth alkaline metals (group 2), in this example strontium, have higher ionization energy than alkaline metals, because they have two valence electrons, they are less reactive.
Rubidium electron configuration: ₃₇Rb 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶5s¹; one valence electron is 5s¹ orbital.
Strontium electron configuration: ₃₈Sr 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶5s²; two valence electrons is 5s² orbital.
Answer:
If a metal is less reactive than carbon, it can be extracted from its oxide by heating with carbon. The carbon displaces the metal from the compound, and removes the oxygen from the oxide. This leaves the metal.
Explanation:
Answer: the percent by mass of potassium nitrate is 13.3%
Explanation:
<u>1) Data:</u>
- Mass of solute, m₁ = 45.0 g
- Volume of solvent, V₂ = 295 ml
- density of water, d₂ = 0.997 g/ml
<u>2) Formulae</u>:
- Percent by mass, % = (mass of solute / mass of solution) × 100
- Density, d = mass / volume
<u>3) Solution</u>:
- d = mass / volume ⇒ m₂ = d₂ × V₂ = 0.997 g/ml × 295 ml = 294. g
- mass of solution = m₁ + m₂ = 45.0g + 294. g = 339. g
- % = (45.0 g / 339. g) × 100 = 13.3 %
- The answer has to be reported with 3 significant figures.
Answer:
9.85% is the mass percent
Explanation:
Mass percent can be determined as mass of solute in 100 g of solution
The solution is soda
Sugar is the solute
(mass of solute / total mass of solution) . 100 =
(33 g / 335g) . 100 = 9.85%
