Answer:
The sun's light is blocked by the moon.
Explanation:
During the eclipse, the moon rotates right in front of the sun, that's why the eclipse is so rare and only happens every four(?) years/
Answer:
422.3868 Grams
Explanation:
13.2 (MOLES) * 31.999 (Dioxygen's Molar Mass) = 422.3868 (Grams Present)
Answer:
sodium=atomic number 11 it electronic configuration is ,K=2, L=8,M=1 Valence is 1
oxygen= atomic number 8 it electronic configuration is K=2, L=6 Valence is 2
iron= atomic number 26 it electronic configuration is K= 2 L= 8,M=8 N=6 Valence 2
Mass of X₄Z₅= 378.621 g
<h3>Further explanation</h3>
Given
3.89 x 10²³ molecules/formula units of X₄Z₅
Required
Mass of X₄Z₅
Solution
1 mol = 6.022 x 10²³ particles(molecules, atoms, ions)
N = n x No
No = Avogadro's number
n = mol
Conversion to mol :
n = N : No
n = 3.89 x 10²³ : 6.022 x 10²³
n = 0.646
MW X₄Z₅ :
= 4 x 76.15 + 5 x 56.3
= 304.6 + 281.5
= 586.1 g/mol
Mass :
= mol x MW
= 0.646 x 586.1
= 378.621 g
Answer:
Cl
Explanation:
⁴¹Ca has an atomic number equal to 20, it means that it has 20 protons and 20 electrons ad its neutral state. In the decay by electron capture, it will lose one electron and will become a cation, but the mass (41) and the atomic number will remain the same.
When Ca⁺ undergoes alpha decay, it will lose an alpha particle, which has mass 4 and 2 protons.
⁴¹₂₀Ca⁺ → ³⁷₁₈X⁺ + ⁴₂α
To be stable, X will lose a proton and will become ³⁷₁₇X. The element which has atomic number 17 is chlorine, Cl.
