Answer:
Explanation:
A molecule is formed when two or more atoms join together chemically. A compound is a molecule that contains at least two different elements. All compounds are molecules but not all molecules are compounds. are not compounds because each is composed of a single element.
Answer:
halogen
Explanation:
It belongs to Group 17 on the periodic table, which is a halogen
The amount left after 20 years = 154.15 mg
<h3>Further explanation
</h3>
The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually radioactive elements have an unstable atomic nucleus.
The main particles are emitted by radioactive elements so that they generally decay are alpha (α), beta (β) and gamma (γ) particles
The decay formula for isotope :

Then for t=20 years, the amount left :

Spectroscopy be used to distinguish between the following is the compound B has a peak at 3200 – 3500 cm⁻¹ in its IR spectrum.
<h3>What is spectroscopy?</h3>
Spectroscopy is the study of emission or absorption of light. It is used to study the structure of atoms and molecules.
The three types of spectroscopy are:
- atomic absorption spectroscopy (AAS)
- atomic emission spectroscopy (AES)
- atomic fluorescence spectroscopy (AFS)
Thus, the correct option is B, the compound B has a peak at 3200 – 3500 cm⁻¹ in its IR spectrum.
Learn more about spectroscopy
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Hello There!
A Heat Pack is An Example Of A Endothermic Process.
An Endothermic Reaction Is A Reaction That Requires Energy To Move Forward.