First, we'll identify the beaker containing pure water as follows:
We'll take equal masses from each of the three beakers and measure the mass of each.
We'll then identify the density of each by using the rule : density =mass/volume
Pure water will be the liquid having density equal to 1 gm/cm^3
Then, we'll differentiate between the salt and sugar solution by measuring the conductivity of each solution. Salt solution is a good conductor while solution of sugar is a bad conductor.
ΔΗ= -115.6 kJ/mol
H2 has a Mr of 2, so as mol=mass/mr we can work out that there are 4 moles of H reacting
Therefore we multiply -115.6 by 4 = -462.4
The correct answer is that it is made of atoms that are covalently bonded together. Hope this helps.
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