Question

A chemical lab sample is known to be made of mercury and oxygen. During an investigation, a 50g sample is decomposed leaving behind 46.5g of pure mercury. Find the percent composition of the amount of mercury in the sample.

Answer 1

The percent composition of mercury in the chemical lab sample is 93%, calculated by dividing the mass of mercury (46.5g) by the total mass of the sample (50g) and multiplying by 100.

Step-by-step explanation:

To find the percent composition of mercury in the lab sample that was originally 50g but left behind 46.5g of pure mercury, we need to carry out a simple calculation. Percent composition is calculated by dividing the mass of the particular element present by the total mass of the compound and then multiplying by 100 to get a percentage.

So for mercury in this sample, we use the formula:

Percent composition of Mercury = (Mass of Mercury / Total Mass of Sample) × 100

Substituting the known values, we get:

Percent composition of Mercury = (46.5g / 50g) × 100 = 93%

Therefore, mercury constitutes 93% of the sample's mass.

Answer 2

The percent composition of mercury in the sample is 93%

STEP-BY-STEP EXPLANATION:

From the question provided, we can see that the sample is a mixture of mercury and oxygen

Given information

• Mass of sample = 50g

,

• Mass of pure mercury = 46.5g

Since the sample is a mixture of mercury and oxygen. We are not given the mass of oxygen in grams that are present in the sample. So, we need to find the mass of oxygen first

Sample = mercury + oxygen

Let the mass of oxygen be x

50 = 46.5 + x

Subtract 46.5 from both sides

50 - 46.5 = 46.6 + x - 46.5

x = 3.5g

From the above calculation, the mass of oxygen in grams in the sample is 3.5g

The next step is to find the % of mercury in the sample using the below formula

`\text{ \% composition of mercury = }\frac{amount\text{ of mercury in grams}}{\text{total amount of the sample in grams}}\cdot\text{ 100\%}`
`\begin{gathered} \text{ \% composition of mercury = }(46.5)/(50)\cdot\text{ 100\%} \\ \text{ \% composition of mercury = }0.93\cdot\text{ 100\%} \\ \text{ \% composition of mercury = 93\%} \end{gathered}`

The percent composition of mercury in the sample is 93%