Answer:
A ability to decompose
B reactivity
Explanation:
Chemical properties are those properties that tell us about what a substance can do as regards to whether or not the substance reacts with other substances.
Examples are flammability, rusting of iron, precipitation, decomposition of water by an electric current.
The ability to decompose and reactivity are chemical properties of a substance.
- Physical properties tells us everything about what a substance is when no change is occurring to its constituents.
- Examples are state of matter, color, odor, taste, texture, hardness e.t.c
Answer: D) helium.
Explanation:
Nuclear fission is a process which involves the conversion of a heavier nuclei into two or more small and stable nuclei along with the release of energy.

Nuclear fusion is a process which involves the conversion of two small nuclei to form a heavy nuclei along with release of energy.
Example: 
Thus when deuterium and tritium , the two isotopes of hydrogen are fused, a heavier nuclei helium is being formed from two smaller nuclei releasing a neutron.
The atomic number (Z) uniquely identifies a chemical element. In an uncharged atom, the atomic number is also equal to the number of electrons.
The atomic number, Z, should not be confused with the mass number, A, which is the number of nucleons, the total number of protons and neutrons in the nucleus of an atom.
In this video Kristine Born explains this two concepts in more detail.
5 Na molecules and 5 Cl molecules
Answer:
3.14
Explanation:
A student was comparing two samples with an equal number of carbon atoms. One sample contained only Carbon-12 atoms. One sample contained only Carbon-14 atoms, which contain two more neutrons than Carbon-12 atoms. The student measured the mass of each sample and testing the reactivity of each sample.
Required:
What would best describe the results of the investigation?