> 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 is: C₄H₈.
C₄H₈ is hydrocarbon, organic compound<span> consisting only of carbon and hydrogen.
CaH</span>₂ (calcium hydride) is alkaline earth hydride, inorganic compound.
H₂O₂(hydrogen peroxide) is pale blue, clear, inorganic <span>liquid.
P</span>₂O₅ (phosphorus pentoxide) is <span>white, crystalline solid inorganic compound.</span>
Answer:
Ice is less dense than water because of the way it forms a hexagonal crystalline structure. Each water molecule consists of two hydrogen atoms bonded to the bottom of an oxygen atom. ... In the winter, temperatures in a lake get close enough to freezing that the colder water is less dense and floats to the top
Explanation:
Freezing could be a good answer
