One mole of copper equals 6.02 × 10^23 atoms. The answer is letter C. This follows the
Avogaro’s law wherein 1 mole of a substance is equal to 6.02 x 10^23 atoms,
formula units or molecules. This is applicable to all substances.
I would say it is a chemical change because after a while, the nails start to rust. Now they only rust after about a week though. But rust is a chemical change.
Every science experiment should follow the basic principles of proper investigation so that the results presented at the end are seen as credible.
Observation and Hypothesis. ...
Prediction and Modeling. ...
Testing and Error Estimation. ...
Result Gathering and Presentation. ...
Conclusions. ...
Law Formation.
Two independent variables could change at the same time, and you would not know which variable affected the dependent variable
