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4 years ago

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Tia has a sample of pure gold (Au). She weighed the sample and the result was 35.9 grams. Tia wants to determine the number of a

toms in the sample. Calculate the number of atoms in 35.9 g of pure gold.

2 answers:

Gemiola [76]4 years ago

4 0

First, find moles of gold given the mass of the sample:
(35.9g Au)/(197.0g/mol Au) = 0.182mol Au

Second, multiply moles of Au by Avogrado's number:
(0.182mol)(6.02 x10^23)= 1.10x10^23 atoms Au

IRINA_888 [86]4 years ago

3 0

Answer: $1.09\times 10^{23atoms$ of gold.

Explanation: To calculate the moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\textMolar mass}}$

For gold

Mass of gold given = 35.9 g

Molar mass of gold = 197 g/mol

Putting values in above equation, we get:

$\text{Moles of gold}=\frac{35.9g}{197g/mol}=0.18mol$

According to Avogadro's law, 1 mole of every substance contains avogadro's number $(6.023\times 10^{23})$ of particles.

Thus 0.18 moles of gold will contain= $\frac{6.023\times 10^{23}}{1}\times 0.18=1.09\times 10^{23}$ atoms of gold.

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Answer:

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Name and Title:

Mitosis and Meiosis Lab Report.

Objective(s):

To learn and explore what mitosis and meiosis is and what they do.

Hypothesis:

Record your predictions during the zoo tour section of the lab in the data chart.

Procedure:

First, go into the mitosis and meiosis cycles. Then look at what happens when a sex cell from a female tiger is combined with a sex cell from a male tiger. Then investigate what happens when two starfish reproduce asexually. Then write down the predictions about how each organism will replicate. Then, keep track on whether or not the forecast was right.

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Record your data from the zoo tour in the data chart below. Be sure to fill in the chart completely.

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