Determine the mass of oxygen that is needed to react with 33 grams of phosphorus. 4P + 5 O2 → 2 P205
A
27.3 grams O2
B
1.33 grams O2
С
213 grams 02
D
42.6 grams 02

D =  42.6 g

Explanation:

Given data:

Mass of oxygen needed = ?

Mass of phosphorus react = 33 g

Solution:

Chemical equation:

4P + 5O₂     →      2P₂O₅

Number of moles of phosphorus:

Number of moles = mass/molar mass

Number of moles = 33 g/ 30.97 g/mol

Number of moles = 1.065 mol

now we will compare the moles of P and oxygen.

                P         :       O₂

                4         :        5

          1.065        :        5/4×1.065 = 1.33mol

Mass of oxygen needed:

Mass = number of moles × molar mass

Mass = 1.33 mol × 32 g/mol

Mass = 42.6 g

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

to explain why this species of moth drinks tears, the scientist could ask: "what nutrients that moths need are in elephant tears? "

the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.