iHub Chem Assessment Unit 1

iHub Chem Assessment Unit 1

by Theresa Paulsen

Poisoned Shopworkers​

​Back in 1920, one of the most sought after jobs on the East Coast was a dial painter at a watch factory. These workers were all female, and they absolutely loved their jobs. These girls were instructed to paint the number on a watch with paint laced with an element called radium. 

Years later, many of these workers developed many medical problems with their bones. Some girls lost their jaw bones, and others’ bones broke when they walked across a room. Several doctors thought that phosphorus poisoned the girls’ bones. Their companies insisted that radium was not damaging their bones in order to avoid a lawsuit.  

• Was it the radium or the phosphorus that poisoned the girls’ bones? 

• Were the factories responsible for the girls’ sicknesses?

​What makes bones weak?

​Calcium from milk and dairy in the diet is stored in bone tissue until humans are in their mid-20s. Calcium moves around the body as an ion. Doctors suspected that another ion - either phosphorus or radium - was deposited instead of calcium in the workers’ bones.

​

How could you figure this out?

Multiple Select

Questions that would help answer the questions:

Was it the radium or the phosphorus that poisoned the girls’ bones? 

Were the factories responsible for the girls’ sicknesses?

• Where are radium, phosphorus and calcium found on the Periodic Table?

• How many valence electrons do P, Ra, and Ca have?

• How many bonds do P, Ra, and Ca form?

• When were P, Ra, and Ca discovered?

Multiple Choice

How many valence electrons does Calcium have?

• 1

• 2

• 3

• 4

Multiple Choice

How many valence electrons does Phosphorus have?

• 2

• 3

• 5

• 6

Multiple Choice

How many valence electrons does Radium have?

• 2

• 4

• 5

• 6

Multiple Choice

Which two elements would bond in the same way?

• Ca and P

• Ca and Ra

• Ra and P

• Ca and O

Multiple Choice

Which is biggest?

• Ca

• Ra

• P

• O

​Identifying patterns

​In 1920, no one knew about ions. Which substance is more likely to be acting as calcium ions in bones of young shopworkers? You identify important patterns in calcium ions compared to radium and phosphorus and determine which element- phosphorus or radium- is more likely to have replaced the calcium ions in the workers’ bodies and caused their ailments.

Multiple Choice

What kind of ion would Ca form?

• 1+

• 2+

• 2-

• 3-

Multiple Choice

What kind of ion would P form?

• 1+

• 2+

• 2-

• 3-

Multiple Choice

What kind of ion would Ra form?

• 1+

• 2+

• 2-

• 3-

Multiple Choice

What is a reason that shopowners might claim Ra might not be replacing Ca in the bones?

• The ions might be too small

• The ions might be too big

• The ions have the wrong charge

• The ions don't bond in the same way.

Multiple Select

What is a reason that shopworkers might claim P would not replace Ca in the bones?

• The ions might be too small

• The ions might be too big

• The ions have the wrong charge

• The ions don't bond in the same way.

Multiple Choice

What is the likely cause of the weakened bones of the girls?

• Ra replacing Ca in the bones

• P replacing Ca in the bones

• Ca replacing Ra in the bones

• Ca replacing P in the DNA

Poll

I found this unit

• Interesting

• Challenging

• Valuable in understanding why Chemistry is important

• Difficult to understand

• Too Slow