Question

1. sucrose is 51.0% oxygen by mass. how many grams of oxygen are in 20.0 g of sucrose? show your work
2. 2.0 g sample of sucrose is 6.50% hydrogen. what is the percent by mass of hydrogen in 300 g of sucrose? explain your reasoning.
3. two compound samples are found to have the same percent by mass of the same elements. what can you conclude about the two samples?

use the law of multiple proportions to answer the questions and complete the table below.
the law of multiple proportions states that if the element x and y form two compounds, the different masses of y that combine with the fixed mass of x can be expressed as a ratio of small whole numbers.

1. two compound samples are composed of the same elements, but in different proportions. what can you conclude about the two samples?

for each compound in the table, fill in the ratio of the mass of oxygen to the mass of hydrogen.

compound	mass of oxygen	mass of hydrogen	mass of o/ mass h
h₂o₂	32 g	2 g	7.

1. are h₂o and h₂o₂ the same compound? explain your answer.

Explanation:

Step1: Calculate the mass of oxygen

Use the formula \(m = \text{mass of sucrose}\times\text{mass percentage of oxygen}\).
Given mass of sucrose \(m_{sucrose}=20.0\ g\) and mass percentage of oxygen \(= 51.0\%=\frac{51.0}{100}\)
\(m = 20.0\times\frac{51.0}{100}\)

Step2: Simplify the expression

\(m=\frac{20.0\times51.0}{100}= 10.2\ g\)

Answer:

\(10.2\ g\)