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vlada-n [284]
2 years ago
6

james needs 4.20 moles of nabr for an experiment. how many grams of nabr must he measure out to have 4.20 moles?

Chemistry
2 answers:
Lena [83]2 years ago
8 0

<u>Ans: Mass of NaBr = 432 g</u>

<u>Given:</u>

# moles of NaBr = 4.20 moles

<u>To determine:</u>

The mass corresponding to 4.20 moles of NaBr

<u>Explanation:</u>

The # moles of a given substance is the ratio of its mass to molar mass

moles = mass (g)/molar mass (g.mol-1)------(1)

Molar mass of NaBr = 102.89 g/mol

Based on equation(1)

mass = moles * molar mass

        = 4.20 moles * 102.89 g.mol-1 = 432 g

kondor19780726 [428]2 years ago
6 0
75.7 grams.
Convert moles to grams using this:

Moles • grams/1 mole = grams

(Grams is over 1 mole)
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