Answer:
Together, the number of protons and the number of neutrons determine an element's mass number. Since an element's isotopes have slightly different mass numbers, the atomic mass is calculated by obtaining the mean of the mass numbers for its isotopes.
Answer:
Q = 217.63J
Explanation:
Data;
Mass = 34.5g
T1 = 26.4°C
T2 = 75.3°C
c = 0.129J/g°C
Energy (Q) = mc(T2 - T1)
Q = 34.5 * 0.129 *(75.3 - 26.4)
Q = 4.4505 * 48.9
Q = 217.629J
Q = 217.63J
The heat gained was 217.63J
9.01 × 10⁻²⁶ J
<h3>Explanation</h3>
ΔE = h · f
Where
- ΔE the change in energy,
- h the planck's constant, and
- f frequency of the emission.
However, only λ is given.
f = c / λ
Where
- f frequency of the emission,
- λ wavelength of the emission, and
- c the speed of light.
For this emission:
f = 2.998 × 10⁸ / 2.21 = 1.36 × 10⁸ s⁻¹.
ΔE = h · f = 6.626 × 10⁻³⁴ × 1.36 × 10⁸ = 9.01 × 10⁻²⁶ J
Answer:
2. (C) K⁺; 3. (E) Hg⁺; 4. Hg⁺
Explanation:
We must first write the electron configurations of the different species.
(A) Fe²⁺
Fe: [Ar]4s²3d⁶
Fe²⁺: [Ar]3d⁶
When removing electrons from a transition metal ion, you remove the s electrons first.
(B) Cl
Cl: [Ne]3s²3p⁵
(C) K⁺
K: [Ar]4s
K⁺: [Ar]
(D) Cs
Cs: [Xe]6s
(E) Hg⁺
Hg: [Xe]6s²4f¹⁴5d¹⁰
Hg⁺: [Xe]6s4f¹⁴5d¹⁰
2. K⁺ has a noble gas configuration
3. Hg⁺ has electrons in f orbitals.
4. The electron configuration of Au is [Xe]6s4f¹⁴5d¹⁰, not [Xe]6s²4f¹⁴5d⁹, because a filled d subshell is more stable than a filled s subshell.
Thus, Hg⁺ is isoelectronic with Au.
Answer:
The question is incomplete.(not enough data provided).
Explanation:
