Helium which has a chemical formula of He is considered as
a noble gas while Nickel which has a chemical formula of Ni is considered as
metallic. Although both have different phases but they are both classified under
the general category of “Elements”.
answer:
<span>elements</span>
Opinion : I disagree recycling can help them, but it still will not clear the environment.
Answer:
Neutral atoms of each element contain an equal number of protons and electrons. The number of protons determines an element's atomic number and is used to distinguish one element from another. ... Together, the number of protons and the number of neutrons determine an element's mass number.
Explanation:
Answer:
Column 17 halogens
Explanation:
To answer the question we need to know the following;
What are valence electrons?
- Valence electrons are outermost electrons in the outermost energy level of an atom of any element.
What are halogens?
- Halogens are group 7 elements that have seven valence electrons. They include, chlorine, fluorine, iodine, etc
What is the reactivity of halogens?
- Halogens are the most reactive non-metals in the periodic table. They react by gaining one electron to attain a stable configuration.