Margaux B.

asked • 10/14/15

I need help with my chemistry assignment




Hi. I do sit-ins at my mum's university because she wanted me to excel in chemistry but I'm only in 8th grade and the lectures my professor gives are in advanced levels. I'm forced to take exams with uni students next week and I need help with my assignment asap. Thanks in advance :)





I already answered three pages but I only need help with some questions.





1. What is the mass of one mole of molecules of Bromine, Dihydrogen, Phosphorus and Oxygen?





2. Complete the following table by filling in the necessary information

Moles of Compound       Moles of Cations       Moles of Anions

1 mol KCI                      _____________      ________________

2 mol Na2SO4                _______________     ________________

0.2 mol calcium nitrate     _____________          ________________

______________             0.50 mol NH4+          0.25 mol SO4^2+




23. The atomic weight of copper is 63.546 amu. The two naturally ocurring isotopes of copper have the following masses: ^63Cu, 62.9298 amu; ^65Cu, 64.9278 amu. Calculate the percent of ^63Cu in naturally occuring copper.

1 Expert Answer

By:

Chia-Ching S. answered • 10/14/15

Tutor
4.9 (18)

New York University STEM Specialist

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