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Assoli18 [71]
4 years ago
7

A chemist weighed out 70.8 g of magnesium. Calculate the number of moles of magnesium she weighed out. Round your answer to sign

ificant digits.

Chemistry
2 answers:
solniwko [45]4 years ago
8 0

Answer:

2.91 grams of Magnesium

Explanation:

I put a picture . I used the molar mass of magnesium which can be calculated from the periodic table or simply google it. :) I hope it helps - Enrique

AlekseyPX4 years ago
4 0
You first take the weighed out amount of magnesium then you divide by the actual mass of magnesium 24.305 g. 70.8/24.305 = 2.912980868134129. Then you multiply by Avagadros number 6.02x10^23. 2.9129 x 6.02x10^23 = 1.753614482617^24. Then round it to 1.75^24 moles of magnesium
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