I think the answer is a pure substance
The formula units in the substances are as follows:
- Br2 = 8.99 × 10^23 formula units
- MgCl2 = 1.51 × 10^24 formula units
- H2O = 2.57 × 10^24 formula units
- Fe = 2.57 × 10^24 formula units
<h3>How many moles are in 239.2 g of the given substances?</h3>
The moles of the substances are determined from their molar mass.
Molar mass of the substances is given as follows:
- Br2 = 160 g/mol
- MgCl2 = 95 g/mol
- H2O = 18 g/mol
- Fe = 56 g/mol
Formula units = mass/molar mass × 6.02 × 10^23
The formula units in the substances are as follows:
- Br2 = 239.2/160 × 6.02 × 10^23 = 8.99 × 10^23 formula units
- MgCl2 = 239.2/95 × 6.02 × 10^23 = 1.51 × 10^24 formula units
- H2O = 239.2/18 × 6.02 × 10^23 = 2.57 × 10^24 formula units
- Fe = 239.2/56 × 6.02 × 10^23 = 2.57 × 10^24 formula units
In conclusion, the number of formula units is derived from the moles and Avogadro number.
Learn more about formula units at: brainly.com/question/24529075
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Answer:
i think its the first one not 100% on it tho but i know for a fact its NOT c
Explanation:
Answer:
D. 20.6g
Explanation:
Molarity is defined as ratio between moles of solute (sodium bromide, NaBr) per liter of water.
As density of water is 1g/mL; volume of 400.0g of water is 400.0mL = 0.4000L.
That means 0.400L of 0.500M solution contains:
0.400L × (0.500mol / 1L) = <em>0.200moles of sodium bromide</em>.
In mass (NaBr = 102.9g/mol):
0.200mol NaBr × (102.9g/mol) = 20.6g of NaBr
Right answer is:
<em>D. 20.6g</em>
