Awater molecule is composed of a large oxygen atom bonded to two small hydrogen atoms. which of the following would make the best model of a water molecule?

a. a drawstring bag filled with blue, green, red, and yellow marbles
b. four index cards printed with either an uppercase or lowercase letter
c. two small, plastic balls attached to a larger plastic ball by toothpicks
d. a large, plastic bucket filled with dirt, dead leaves, and rocks

Calculate the number of moles of ethane in 100 grams

Most materials are not magnetic because their magnetism has worn off. their magnetic domains are arranged randomly. they lack magnetic fields. earth’s heat has destroyed their magnetism.

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.