In the presence of dissolved oxygen, microorganisms can oxidize

nitrite ions (no–2) to nitrate ions (no–3) via the following reaction:

no−2 + 0.5 o2(aq) −−→ no−3

(a) this reaction is occurring in a batch bioreactor at a rate that is first order with respect
to both no–2 and o2(aq), with k2=3×10^4 l/mol·d . how much time is required for the nitrite
concentration to be reduced from 0.3 mm to 0.1 mm if o2 is resupplied continuously to maintain
the o2(aq) concentration at 4mg/l?

Label a-f based on the table using c for concentrated and d for dilute

Why is the bond angle in a water molecule less than the bond angle of methane? a. the central oxygen atom in water has two lone pairs of electrons, whereas the central carbon atom in methane has no lone pairs. b. the central hydrogen atom in water has one lone pair of electrons, whereas the central carbon atom in methane has two lone pairs. c. the central oxygen atom in water has four lone pairs of electrons, whereas the central carbon atom in methane has only one lone pair. d. the central oxygen atom exerts more repulsive force on surrounding atoms than the central carbon atom in methane does. reset next

7. in the cycle, a virus integrates its dna into the host's dna, and its dna is replicated when the host dna is replicated. a. infectious b. retroviral c. lysogenic d.lytic