Answer: Let's see why
Pure solid and liquid compounds possess sharp melting and boiling points. Therefore, melting and boiling points of a compound can be used as a criteria of purity. ... Sometimes during cooling minute quantity of the substance (solid which is being purified) is added to the solution to facilitate the initial crystallisation.
Explanation:
Answer:
Mass of hydrogen produced =2.28 g
Explanation:
Given data:
Mass of tin = 67.3 g
Mass of hydrogen produced = ?
Solution:
Chemical equation:
Sn + 2H₂O → SnO₂+ 2H₂
Number of moles of Sn:
Number of moles = mass/ molar mass
Number of moles = 67.3 g/ 118.71 g/mol
Number of moles = 0.57 mol
Now we will compare the moles of tin with hydrogen from balance chemical equation.
Sn : H₂
1 : 2
0.57 : 2×0.57 = 1.14
Mass of hydrogen:
Mass = number of moles ×molar mass
Mass = 1.14 mol × 2 g/mol
Mass = 2.28 g
You can estimate by finding the measure/weight of a single penny and then finding the measure/weight of an empty coffee cup. Once you have that, weigh the whole thing and then go from there to find the amount of pennies :)
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