Question

Which of these chemical formulas kci, xe, co2, or h2- represents both an element and a molecule?

Answer 1

Answer:

The answer is Xe

Explanation:

An element is a substance that cannot be broken down by an ordinary chemical process. Atoms of the same elements contain the same number of protons. The periodic table has all the elements currently used in chemistry and can be a guide in determining elements.

A molecule is an electrically neutral substance usually containing one or more group of atoms.

All the options provided in the question are molecules but all options other than Xenon (Xe) and hydrogen gas (H2) are compounds. A compound is a substance made up of two or more different atoms held together by chemical bonds. From this definition, we can see that both potassium chloride (KCl) and carbon dioxide (CO2) are compounds as they are made up of different atoms. KCl has both potassium (K) and chlorine (Cl) while CO2 has both carbon (C) and oxygen (O).

Hydrogen gas (H2) is a molecule but it has two atoms of hydrogen and cannot represent hydrogen element because it is denoted as H2 while what is in the periodic table of elements is represented as H. The reason an atom cannot be represented as an element is because an atom is the smallest particle of an element that can take part in a chemical reaction and still maintain its chemical properties. H2 is what can take part in a chemical reaction, not H.

Xenon (Xe) is an element that can be found in the periodic table. It has an atomic number of 54 and it is found in the group zero of the periodic table. Elements found in group zero are called noble gases because they are stable (electrically neutral) which makes them resist undergoing chemical reaction. These elements (in this case Xe) also exist naturally (alone) because they are electrically neutral and can hence be referred to as a molecule and an element.

Answer 2

An element is a substance that can not be broken into simpler parts by chemical means. Elements are made up of atoms. A molecule is the smallest particle of an element or a compound that has the same properties as the element or the compound. A molecule is made up of two or more atoms . A substance may be an element and a molecule. In this case the answer is, H2 (hydrogen gas) which is a molecule with two atoms of hydrogen and an element.