The nucleus of 8Be, which consists of four protons and four neutrons, is very unstable and spontaneously breaks into two alpha particles (helium nuclei, each consisting of two protons and two neutrons). True or false?

The given statement is false.

Explanation:

When there is more difference in the ratio or number of protons and neutrons then nucleus of the atom becomes unstable in nature. This unstability is caused due to greater repulsion between the like charges of sub-atomic particles.

As a result, this force of repulsion becomes greater than the binding energy. And, this force is known as the weak force because it is unable to bind the neutrons and protons together.

The proton and neutron ratio for smaller elements is 1:1 and for higher elements it has to be 1:5. Since, is a smaller element with 4 protons and 4 neutrons. Hence, the proton and neutron ratio is 1:1.

Therefore, is stable in nature.

Thus, we can conclude that the statement nucleus of 8Be, which consists of four protons and four neutrons, is very unstable and spontaneously breaks into two alpha particles (helium nuclei, each consisting of two protons and two neutrons), is false.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.