The new Online Chemistry Curriculum created by the National Science Teachers Association
Free - online Middle school Chemistry curriculum that correlates with national standards
http://www.middleschoolchemistry.com/
Khan Academy's CRASH COURSE IN CHEMISTRY https://www.khanacademy.org/partner-content/crash-course1/crash-course-chemistry/v/chem01-the-nucleus?utm_source=Sailthru&utm_medium=email&utm_term=Stuff%20you%20might%20like%20After%20Test%20Cohort%20Made&utm_campaign=Highlighted%20Content%20031515%20-%20Second%20List%20%5BFinal%5D
AP Chemistry at Khan Academy
Stoichiometry at Khan Academy
There are 7 BASE units of Measurement
Chemestry Calculator https://www.symbolab.com/solver/chemistry-calculator
Liters to Grams https://www.convertunits.com/from/liters/to/grams
Moles Converter http://www.endmemo.com/chem/mmass.php Chemical Mole Gram Calculator