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For ai it's atomic number is 13 and it's mass number is 27 how many neutrons does it have

Use examples from the article to explain one positive and one negative effect that chemistry has had on society.

After watching the video "zinc strip in copper nitrate solution", and reading the instructions, click on the link labeled "start" just below the drawing of the pencil tip. follow the direction to complete the 3x3 grid. answer the below questions for the portion of the activity in which sn(s) is placed in agno3(aq)