A mystery element "A" has two stable isotopes X-100 which occurs 20% of the time and X-120 which occurs 80% of the time. What is the average mass of element "A"?

A-100 amu

B-104 amu

C-116 amu

D-120 amu

In the following redox reaction which is the oxidizing agent and which is the reducing agent? alcl3 + na nacl + al oxidizing agent = reducing agent =

Consider the following unbalanced equation for the combustion of hexane: αc6h14(g)+βo2(g)→γco2(g)+δh2o(g) part a balance the equation. give your answer as an ordered set of numbers α, β, γ, use the least possible integers for the coefficients. α α , β, γ, δ = nothing request answer part b determine how many moles of o2 are required to react completely with 5.6 moles c6h14. express your answer using two significant figures. n n = nothing mol request answer provide feedback

What is the correct lewis dot structure for arsenic?