Did you observer any chemical changes in this experiment?
Yes
What evidence did you use to decide that something was a chemical change? I observed during the application of the hydrochloric acid to some of the substances bubbling, and smoking
Give at least two examples of chemical changes you observed. Green changed
from blue to application of HCL to Mg smoking and bubbling and CuCO3
Classify the following properties of sodium metal as physical or chemical:
• Silver metallic color: Physical
• Turns gray in air: Chemical
• Melts at 98oC: Physical
• Reacts explosively with chlorine gas: Chemical
Classify the following changes as physical or chemical:
• Water freezes at 0oC: Physical
• Baking soda when combined with vinegar produces bubbles: Chemical
• Mothballs gradually disappear at room temperature: Physical
• Ice cubes in a freezer get smaller with time: Physical
• Baking soda loses mass as it is heated: Chemical
• Tarnishing of silver: Chemical
How would you show that dissolving table salt is a physical change? Because the salt doesn’t change to something else, it stays salt. Boil the water and the salt will still be there, not something else.
Cleanup: Mix the leftover sodium hydroxide and hydrochloric acid in your beaker. This will neutralize them. Now, pour them down the drain with lots of water. Place the small amount of solid chemicals left (if any) in a small plastic bag and put it in the trash. After the burner fuel has completely cooled, screw the cap on tightly and store it in your LabPaq.
The Essay on Physical Changes in Adolescence
Children must pass through several stages, or take specific steps, on their road to becoming adults. According to the U.S Department of Health and Human Services the term adolescence is commonly used to describe the transition stage between childhood and adulthood. Adolescence is also equated to both the terms “teenage years” and “puberty.” They also state that puberty refers to the “hormonal ...
