Answer:
Chemistry is another word for science just higher level.the branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances.
Explanation:
Its very hard to answer all of these questions
According to this formula :
ΔTf= i Kf m
i is van't Hoff factor= 1
Kf = 1.86
m the molality we need to assume it
m= x moles of C2H5OH / Kg of mass
∴ 15 = 1 * 1.86 * ( x moles of C2H5OH/ 0.45 kg)
∴X = 3.629 moles
mass = no.of moles x molar mass of C2H5OH
= 3.629 X 46 = 167 g
∴the volume = mass / denisty
= 167 / 0.7893 = 211.57≈ 212 mL
Answer: pOH = 3.13
Ba(OH)2 is a very basic substance. The general formula for pOH is - log(OH)
Barium Hydroxide produces 2 moles of OH for every mole of Ba(OH)2 present in the solution.
0.00037 M = 3.7 * 10^-4 Ba(OH)2 will produce 2 *0.00037 M of OH-
OH- = 2* 0.00037 = 0.00074
pOH = - log(0.00074) = 3.13