Tutor profile: Sanjana P.

If 6x-3y=18, then what is the value of [81^(x)] / [9^(y)]? (a) 9^2 (b) 6^9 (c) 9^9 (d) 9^6

(d) 9^6 [81^(x)]/[9^(y)] = [9^(2x)]/[9^(y)]=9^(2x-y) 6x-3y=18 (1/3)[6x-3y]=(1/3)[18] 2x-y=6 Therefore, after plugging in: 9^(2x-y)=9^6

Katrina is struggling to identify the nucleophile and electrophile in a basic organic chemistry reaction. What characteristics make a molecule nucleophilic? What makes a molecule electrophilic?

The nucleophile of a chemical reaction is the species that donates an electron/electron pair and tends to have an overall negative charge or have at least one pi bond. The electrophile of a chemical reaction is the species that accepts the donated electron/electron pair and tends to have an overall positive charge.

Tim has been very stressed because of his new, hectic job. In his most recent check-up, Tim's doctor diagnosed him with elevated blood pressure. His doctor prescribed a medication that will affect Tim's cardiac output and vessel stretch to drop his blood pressure. How is the medication going to affect Tim's cardiac output and vessel stretch?

Tim's prescribed medication will ultimately decrease cardiac output and increase vasodilation (or dilation of the blood vessels). This is achieved by increasing baroreceptor firing to trigger increased activity in cardiac inhibitory centers, as well as decreased activity in cardiac accelerator centers and vasomotor centers.