The question is incomplete; the complete question is;
There are 118 known elements. How many elements have atoms, in their ground state, with core electrons whose quantum numbers are n=3 and l=1?
a. 10
b. 6
c. 100
d. 18
Answer:
c. 100
Explanation:
If we look closely at the periodic table, we will notice that there 100 elements that occur after argon whose electronic configuration is; 1s2 2s2 2p6 3s2 3p6.
This means that there every other element after argon must have a 3p sublevel as part of its core electrons. In the 3p sublevel, n=3 and l=1.
If we diligently count the number of elements from potassium (immediately after argon) to Oganesson (element 118) we have a total of 100 elements all having core electrons of quantum numbers are n=3 and l=1.
Answer:
Two
Explanation:
In chemical equations, the number of atoms of each element in the reactants must be the same as the number of atoms of each element in the products.
Answer:
65.47∘C
Explanation:
Specific heat capacity, c = 0.128 J/(g⋅∘C)
Initial temperature = 20.0 ∘C
Final temperature = ?
Mass = 52.4 g
Heat = 305 J
All these variables are related by the following equation;
H = m c ΔT
ΔT = H / mc
ΔT = 305 / (52.4 * 0.128)
ΔT = 45.47∘C
ΔT = Final Temperature - Initial Temperature
Final temperature = ΔT + Initial temperature
Final temperature = 45.47∘C + 20.0 ∘C = 65.47∘C
Answer:
Neutron
Explanation:
Neutrons has a neutral or no charge.
Answer:
1. Balanced molecular equation:
- HF(aq) + RbOH(aq) → RbF(aq) + H₂O(l)
2. Net ionic equation:
- H⁺ (aq) + OH⁻ (aq) → H₂O(l)
Explanation:
<u>1. Write the word equation</u>
This is the reaction of an acid and a base producing salt plus water.
- hydrofluoric acid + rubidium hydroxide → rubidium fluoride + water
<u>2. Balanced molecular equation</u>
- HF(aq) + RbOH(aq) → RbF(aq) + H₂O(l) ← answer
<u />
<u>3. Write the ionic compounds in aqueous solution as ions</u>
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Overall ionic equation:
- H⁺ (aq) + F⁻ (aq) + Rb⁺ (aq) + OH⁻ (aq) → Rb⁺ (aq) + F⁻ (aq) + H₂O(l)
<u>4. Cancel the spectator ions</u>
The spectator ions are those that appear in both sides of the overall ionic equation. In this case they are F⁻ (aq) and Rb⁺ (aq).
Net ionic equation:
- H⁺ (aq) + OH⁻ (aq) → H₂O(l) ← answer
