Answer: fourth option, 10.8 kJ
Explanation:
The <em>heat of fusion</em>, also named latent heat of fusion, is the amount of heat energy required to change the state of a substance from solid to liquid (at constant pressure).
The data of the <em>heat of fusions</em> of the substances are reported in tables and they can be shown either per mole or per gram of substance.
In this case we have that the<em> heat of fusion for water </em>is reported per mole: <em>6.02 kJ/mole</em>.
The formula to calculate <em>how many kJ of heat (total heat) are needed to completely melt 32.3 g of water, given that the water is at its melting point</em> is:
- Heat = number of moles × heat of fusion
The calculations are:
- number of moles = mass / molar mass
number of moles = 32.3 g / 18.015 g/mol = 1.79 mol
- Heat = 1.79 mol × 6.02 kJ / mol = 10.8 kJ ← answer
The mass of a 0.513 mol of Al2O3 is 52.33g.
HOW TO CALCULATE MASS:
The mass of a substance can be calculated by multiplying the molar mass of the substance by its number of moles. That is;
mass of Al2O3 = no. of moles of Al2O3 × molar mass of Al2O3
According to this question, there are 0.513 moles of Al2O3.
Mass of Al2O3 = 0.513 × 102
Mass of Al2O3 = 52.33g
Therefore, the mass of a 0.513 mol of Al2O3 is 52.33g.
Learn more about mass calculations at: brainly.com/question/8101390?referrer=searchResults
C. Developing effective methods of food preservation
Explanation:
The development of effective methods of food preservation is a much more smaller and manageable problem that contributes to the complex problem.
The percentage of food rotting is not as a result of lack of an effective preservation technique as highlighted in the passage. It is due to the long distances of agricultural area from where the farms are located.
- To cut the loss, efficient and rapid transportation techniques needs to be put in place to carry the fruits and vegetables to the area where they are needed.
- This is the most complex problem that if solved can peg back food rot.
- Additional measures should be put in place to preserve the food.
Other options does not address the subject matter
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Preservation brainly.com/question/4853419
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I believe it is d, a microhabitat is a small area which differs somehow from the surrounding habitat. Its unique conditions may be home to unique species that may not be found in the larger region.
