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kow [346]
3 years ago
6

What sample size (grams) of Na3PO4 (FW 164.00) known to be 50.00% pure should be used to consume exactly 40.00 mL of 0.1000 M HC

l to reach the 2nd end point
Chemistry
1 answer:
Mkey [24]3 years ago
3 0

Answer:

0.109 g.

Explanation:

Equation of the reaction:

Na3PO4 + 3HCl --> 3NaCl + H3PO4

Number of moles of HCl = molar concentration × volume

= 0.1 × 0.04

= 0.004 mol.

By stoichiometry, 1 mole of Na3PO4 neutralises 3 moles of HCl. Therefore, number of moles of Na3PO4 = 0.004/3

= 0.0013 mol

Mass of Na3PO4 = molar mass × number of moles

= 0.0013 × 164

= 0.219 g

Since 50% of Na3PO4 was present in the sample. Let 100 g be the total mass of the substance

= 0.219 × 50 g/100 g

= 0.109 g.

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Explanation:

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At what temperature does uranium hexafluoride have a density of 0.9560 g/L at 0.5073 atm?
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3 years ago
The specific heat of zinc is 0.39 J/g*°C. How much energy needed to change the temperature of 34g of zinc from 22°C to 57°C. Is
Svetlanka [38]

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464.1 J absorbed.

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