Answer:
2.4 g
Explanation:
Step 1: Given data
- Initial pressure (P₁): 755 torr
- Final pressure (P₂): 1.87 atm
Step 2: Convert "P₁" to atm
We will use the conversion factor 1 atm = 760 torr.
755 torr × 1 atm/760 torr = 0.993 atm
Step 3: Convert "T" to K
We will use the following expression.
K = °C + 273.15
K = 25°C + 273.15 = 298 K
Step 4: Calculate the initial number of moles of He
We will use the ideal gas equation.
P₁ × V = n₁ × R × T
n₁ = P₁ × V/R × T
n₁ = 0.993 atm × 16.8 L/(0.0821 atm.L/mol.K) × 298 K
n₁ = 0.682 mol
Step 5: Calculate the final number of moles of He
We will use the ideal gas equation.
P₂ × V = n₂ × R × T
n₂ = P₂ × V/R × T
n₂ = 1.87 atm × 16.8 L/(0.0821 atm.L/mol.K) × 298 K
n₂ = 1.28 mol
Step 6: Calculate the moles of He added
n = n₂ - n₁
n = 1.28 mol - 0.682 mol
n = 0.60 mol
Step 7: Convert "n" to mass
The molar mass of He is 4.00 g/mol
0.60 mol × 4.00 g/mol = 2.4 g
<span>The s sublevel has just one orbital, so can contain 2 electrons max. The p sublevel has 3 orbitals, so can contain 6 electrons max. The d sublevel has 5 orbitals, so can contain 10 electrons max. And the 4 sublevel has 7 orbitals, so can contain 14 electrons max.
So, having this in mind, 10 electrons in total can be contained in the 4d sublevel.
</span>
Answer:
D) Energy stored in molecular bonds
Explanation:
Hope this helps you
The very last option is the correct answer.
Answer:
Net ionic equation:
Ba²⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)
Explanation:
Chemical equation:
BaCl₂ + Na₂SO₄ → BaSO₄ + NaCl
Balanced Chemical equation:
BaCl₂(aq) + Na₂SO₄(aq) → BaSO₄(s) + 2NaCl(aq)
Ionic equation:
Ba²⁺(aq) + 2Cl⁻(aq) + 2Na⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)+ 2Na⁺(aq) + 2Cl⁻ (aq)
Net ionic equation:
Ba²⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)
The Cl⁻(aq) and Na⁺ (aq) are spectator ions that's why these are not written in net ionic equation. The BaSO₄ can not be splitted into ions because it is present in solid form.
Spectator ions:
These ions are same in both side of chemical reaction. These ions are cancel out. Their presence can not effect the equilibrium of reaction that's why these ions are omitted in net ionic equation.