Which of these pairs of elements have the same number of valence electrons?

a) hydrogen (h) and helium (he)

b) sodium (na) and potassium (k)

c) carbon (c) and oxygen (o)

d) boron (b) and beryllium (be)

If a solution had a ph of 7 what is the solution

Which factor is likely to impact the possible number of compounds ?

Which activity describes an application of topographic maps? check all that apply. recreation, such as camping and hiking engineering, such as the construction of roads and buildings science, such as mapping stars in the sky business, such as analyzing population centers science, such as analyzing surface features