Answer:
Potassium
General Formulas and Concepts:
<u>Chem</u>
- Reading a Periodic Table
- Periodic Trends
- Ionization Energy - energy required to remove an electron from a given element
- Coulomb's Law
- Shielding Effect
- Z-effective and Forces of Attraction
Explanation:
The Periodic Trend for 1st Ionization Energy is increasing up and to the right. That means He would have the highest I.E and therefore take the most amount of energy to remove an electron.
Potassium and Gallium are both in Period 4. Potassium is element 19 and Gallium is element 31.
Potassium's electron configuration is [Ne] 4s¹ and Gallium's electron configurations is [Ne] 4s²3d¹⁰4p¹. Since both are in Period 4, they have the same number of core e⁻. Therefore, the shielding effect is the same.
However, since Gallium is element 31, it has 31 protons compared to Potassium, which is element 19 and has 19 protons. Gallium would have a greater Zeff than Potassium as it has more protons. Therefore, the FOA between the electrons and nucleus of Ga is much stronger than that of K. Thus, Ga requires <em>more</em> energy to overcome those FOA to remove the 4p¹ e⁻. Since K has less protons, it will have a smaller Zeff and thus less FOA between the e⁻ and nucleus, requiring <em>less</em> energy to remove the 4s¹ e⁻.
Answer:
The percentage by mass of benzene in the solution is approximately 0.2%
Explanation:
The given parameters are;
The mass of the benzene solute dissolved in the gasoline solvent, m₁ = 1.56 g
The total volume of the benzene gasoline solution made, V = 998.44 mL
The density of gasoline, ρ = 0.7489 g/mL
Mass, m = Density, ρ × Volume, V
∴ The mass of gasoline in the 998.44 mL, solution = 0.7489 g/mL × 998.44 mL = 747.731716 g
The total mass of the solution = The mass of the benzene in the solution + The mass of the gasoline in the solution
∴ The total mass of the solution = 747.731716 g + 1.5 g = 749.231716 g

The percentage by mass of benzene in the solution = (1.5 g/749.231716 g)×100 ≈ 0.2% by mass.
Answer: magnet, fridge and uh......metal
Explanation:
Answer:
Volume is the amount of space taken up an object.