10 POINTS PLS HELP ASAP WILL MARK BRANLIEST
An environmental problem with landfills is
A.
incomplete decomposition.
B.
all of these.
C.
groundwater pollution.
D.
methane production.

Zoe is investigating the composition of substance a, an unknown substance. using chemical processes, she analyzes substance a and determines it is composed of sodium, oxygen, and hydrogen atoms in a ratio of 1 : 1 : 1. what is substance a? a. a compound b. an element c. a heterogeneous mixture d. a homogeneous mixture

Part b: study of equilibrium on solubility: mg(oh)2(s) ⇌ mg2+(aq) + 2 oh–(aq) cloudy clear (pink) 7. a. b. 8. a. b. 9. 10. 11. 12. when adding concentrated hydrochloric acid, how did the appearance of the equilibrium mixture change? the change in appearance indicated a shift in the point of equilibrium. in which direction did the equilibrium shift? (l) left (r) right explain your answer to question 7a. you should indicate which ion was added to or removed from the equilibrium mixture. when adding edta, how did the appearance of the equilibrium mixture change? the change in appearance indicated a shift in the point of equilibrium. in which direction did the equilibrium shift? (l) left (r) right explain your answer to question 8a. you should indicate which ion was added to or removed from the equilibrium mixture. upon heating in which direction is the equilibrium shifting? upon cooling in which direction is the equilibrium shifting? is the forward reaction a. endothermic explain your answers to questions 9, 10, and 11. (l) left (r) right (l) left (r) right b. exothermic

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