The student performed an experiment to test his hypothesis about sunlight and plant height using two plants. He kept everything the same between two tomato plants except he exposed them to different amounts of sunlight. He also used a third plant as a control group, or a group in which no variables are manipulated to confirm the results. Roberto critiqued the work. Which problem did Roberto most likely identify? 1.The sample size is too small. 2.Too many variables are manipulated. 3.It is not possible to keep the conditions the same. 4.Controls should only be used in studies of animals.

Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.

How many atoms are in 2 moles of phosphorus?

Abaker touches a pie right after taking it out of the oven. which statement best explains why the pie feels hot?