> How many valence electrons does a helium atom have?
The electron configuration of Helium is simply 1s2. We see
that its outermost shell is the s shell and it contains 2 electrons, therefore
the number of valence electrons is also 2.
> What is the formula of the ion formed when potassium
achieves noble-gas electron configuration?
Potassium has a electron configuration of [Ar] 4s1. To
have an electron configuration of only [Ar] which is a noble gas, the one electron
from 4s1 should be removed, hence:
<span>K+</span>
Answer:
B
Explanation:
Blue triangles are a cold front and red bowls are warm front
Stationary front is a combination
HOPE I helped :]
Answer is: volume of carbon dioxide is 1,84·10⁸ l.
Chemical reaction: C + O₂ → CO₂.
m(C) = 100 t · 1000 kg/t = 100000 kg
m(C) = 100000 kg · 1000 g/kg = 10⁸ g.
n(C) = m(C) ÷ M(C).
n(C) = 10⁸ g ÷ 12 g/mol.
n(C) = 8,33·10⁶ mol.
From chemical reaction: n(C) . n(CO₂) = 1 : 1.
n(CO₂) = 8,33·10⁶ mol.
m(CO₂) = 8,33·10⁶ mol · 44 g/mol.
m(CO₂) = 3,66·10⁸ = 3,66·10⁵ kg.
V(CO₂) = 3,66·10⁵ kg ÷ 1,98 kg/m³ = 1,84·10⁵ m³.
V(CO₂) = 1,84·10⁵ m³ · 1000 l/m³ = 1,84·10⁸ l.