A compound consists of 3 moles of carbon and 4 moles of hydrogen. What is the empirical formula of this compound? Group of answer choices

CH4

C3H3

C3H4

C4H3

Which element in the third period would you expect to have the larger atomic radius, sodium (na) or sulfur (s)? a. sodium, because it has a higher effective nuclear charge attracting electrons in fewer energy levels. b. sodium, because it has fewer protons attracting electrons in the same energy levels. c. sulfur, because it has more protons attracting electrons in more energy levels. d. sulfur, because it has a higher effective nuclear charge attracting electrons in the same energy levels.

The rules of engagement (roe) working group is often used to (select all that apply.)

What causes the appearance of lines in a emission spectrum