Question

hydrogen and oxygen combine to form water. this is an example of what type of change?
select one:
a. electrical
b. chemical
c. nuclear
d. physical

the type of change occurring when a nucleus emits particles and energy and a new element is formed is...
select one:
a. a chemical change.
b. an electrical change.
c. a physical change.
d. a nuclear change.

Explanation:

1. For the first question: When hydrogen and oxygen react to form water, new chemical bonds are created, and a new substance (water) is produced from the original reactants. This fits the definition of a chemical change, which involves the formation of new substances.
2. For the second question: A change that involves the nucleus of an atom, emits particles/energy, and forms a new element is defined as a nuclear change, as it alters the atomic nucleus rather than just chemical bonds or physical properties.

Answer:

1. b. Chemical
2. d. a nuclear change.