Why do elements in a group on the periodic table have similar chemical properties?
a. similar atomic masses
b. similar atomic numbers
c. same number of outermost electrons
d. same number of protons

Titania buys a bag of fertilizers at the store.it reads 30-15-10. how much phosphorous is in the fertilizer a. 30% b. 15% c. 10%

Asample of the male sex hormone testosterone, c19h28o2, contains 3.88×10^21 atoms of hydrogen.(a) how many atoms of carbon does it contain? (b) how many molecules of testosterone does it contain? (c) how many moles of testosterone does it contain? (d) what is the mass of this sample in grams?

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