Answer:
Potassium is an element that has 19 electrons
Explanation:
Standard formation of an substance is defined as formation of one mole of substance from its constituting elements.
Chromium(III) nitrate is composed of chromium, nitrogen and three oxygen atoms.

A balanced chemical equation for the standard formation reaction of solid chromium(III) nitrate

Using the Avogadro's number (6.022*10^23)
9.11* (6.022*10^23)= 5.49*10^24 atoms of V
the answer is A.) because the scientific method is used to answer problems.
This is the steps,
STEP 1: ask a question
STEP 2: state your hypothesis
STEP 3: conduct an experiment
STEP 4: analyze your results
STEP 5: make a conclusion
The chemical formula of butane is C4H10.