Chemistry lab;Counting Atoms

1.Start Virtual ChemLab, select Reactions and Stoichiometry, and then select Counting Atoms (2) from the list of assignments. The lab will open in the Calorimetry laboratory. 

2.Enter the stockroom by clicking inside the Stockroom window. Once inside the stockroom, click on the Metals cabinet and then open the third drawer by clicking on it. When you open the drawer, a Petri dish will appear on the counter next to the cabinet. Place the sample of lead (Pb) found in the drawer into the sample dish by double-clicking on the sample or by clicking and dragging it to the dish. Return to the stockroom view by clicking on the green Zoom Out arrow. Place the Petri dish on the stockroom counter by double-clicking on it or by clicking and dragging it to the counter. Click on the Return to Lab arrow to return to the laboratory. 

3.Drag the Petri dish to the spotlight near the balance. Click on the Balance area to zoom in. Drag a piece of weighing paper to the balance pan, Tare the balance, and then drag the lead sample to the balance pan and record the mass. 
Mass =

4.Calculate the moles of Pb contained in the sample.

5.Calculate the atoms of Pb contained in the sample.

6.Repeat steps 2-5 for uranium. Record the mass, the moles, and the atoms of uranium. 

Mass of uranium =

Moles of uranium =

Atoms of uranium =

Sample Solution