Answer:
The melting point range of a substance is the temperature range from which the first crystal starts to melt, to the temperature at which the last crystal finishes melting. An impure substance is a type of mixture, so melting points can be used to find out if a substance is pure or impure.
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Explanation:
When 3.66 g of KOH (∆Hsol = -57.6 kJ/mol) is dissolved in 150.0 mL of solution, it causes a temperature change of 5.87 °C.
The enthalpy of solution of KOH is -57.6 kJ/mol. We can calculate the heat released by the solution (Qr) of 3.66 g of KOH considering that the molar mass of KOH is 56.11 g/mol.
According to the law of conservation of energy, the sum of the heat released by the solution of KOH (Qr) and the heat absorbed by the solution (Qa) is zero.
150.0 mL of solution with a density of 1.02 g/mL were prepared. The mass (m) of the solution is:
Given the specific heat capacity of the solution (c) is 4.184 J/g･°C, we can calculate the change in the temperature (ΔT) of the solution using the following expression.
When 3.66 g of KOH (∆Hsol = -57.6 kJ/mol) is dissolved in 150.0 mL of solution, it causes a temperature change of 5.87 °C.
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Answer:
Hey mate, here is your answer. Hope it helps you.
Explanation:
To show how substances in a chemical reaction interact and to keep track of all elements and the number of atoms in each element on each side of the equation.The purpose of writing a balanced chemical equation is to know: the reactants (starting material) and products (end results) that occur. the ratios in which they react so you can calculate how much reactants you need and how much products can be formed.
Answer:
- contains oxygen
- provides warmth
- blocks harmful energy from the Sun
Explanation:
The atmosphere is crucial when it comes to providing living conditions on Earth. The gases in the atmosphere manage to balance the things just about right, so that the life can thrive. The atmosphere has oxygen, the gas that is used by pretty much every organism to be able to function. With its greenhouse gases, the atmosphere manages to trap the heat inside, thus providing warmth to the Earth. The numerous layers of the atmosphere manage to block in big portion the harmful energy from the Sun, with a special accent on the ozone layer, a layer that manages to stop most of the UV radiation.
Answer:
In comparison to Part 1 of this experiment, we observed similar reactions when determining the make up of our unknown. When testing for Mn2+ we observed a color change that resulted in a darker brown/red color, when testing for Co2+ we observed the formation of foamy bubbles but we could not conclude that a gas had formed, when testing for Fe3+ the result was a liquid red in color, when testing for Cr3+ we observed no change, when testing for Zn2+ we observed the formation of a pink/red liquid, when testing for K+ we observed the formation of a precipitate, when testing for Ca2+ we observe the formation of a precipitate. Sources of error may have occurred when observing whether or not an actual reaction had taken place or not, using glassware that wasn't fully cleaned, or the accidental mix of various other liquids in the lab
Explanation:
