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1 answer:
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Answer: 9.09 %
Explanation:
To calculate the percentage concentration by volume, we use the formula:
Volume of ethanol (solute) = 30 ml
Volume of water (solvent) = 300 ml
Volume of solution= volume of solute + volume of solution = 30+ 300 = 330 ml
Putting values in above equation, we get:
Hence, the volume percent of solution will be 9.09 %.
The enthalpy change for melting ice is called the entlaphy of fusion. Its value is 6.02 kj/mol. This means for every mole of ice we melt we must apply 6.02 kj of heat. We can calculate the heat needed with the following equation:
Q = N x ΔH
where:
Q = heat
N = moles
ΔH = enthalpy
In this problem we would like to calculate the heat needed to melt 35 grams of ice at 0 °C. This problem can be broken into three steps:
1. Calculate moles of water
2. multiply by the enthalpy of fusion
3. Convert kJ to J.
Step 1 : Calculate moles of water
Step 2 : Multiply by enthalpy of fusion
Q = N × ΔH = <em> [ Step 1 Answer ]</em> × 6.02 =
Step 3 : Convert kJ to J
Finally rounding to 2 sig figs (since 34°C has two sig figs) we get
Q Would Equal ____