Answer:
2.41065 grams
Explanation:
Here we have to apply molarity, particularly in reference to the equation molarity = moles of solute / volume. I would like to rewrite this formula, but with respect to the units - grams = moles / Liters,
We can use molarity to determine the number of moles. After doing so, we can determine the mass of the solute with respect to the formula moles = mass / molar mass. The molar mass of NaCl is 58.44 grams.
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275 mL = 0.275 L,
Number of Moles of NaCl = 0.150 * 0.275 = 0.04125 moles,
Mass = 0.04125 * 58.44 = 2.41065 grams,
Solution - Mass of NaCl = 2.41065 grams
<u><em>Hope that helps!</em></u>
Answer: C. ethanol
The enthalpy of combustion is the amount of heat produced when one mole of ethanol undergoes complete combustion at 25 ° C and 1 atmosphere pressure, yielding products also at 25 ° C and 1 atm.
<u>The enthalpy of combustion of the unknown compound is</u>
ΔH = - 320 kJ / 0.25 mol = - 1280 kJ / mol
<u>To choose a probable compound according to this combustion enthalpy, we must evaluate the deviation in relation to the values reported in the literature for the three probable compounds</u> (methane, ethylene and ethanol). The deviation (e%) will be calculated according to the following equation,
e% = ( | ΔHx - ΔH | / ΔHx ) x 100%
where ΔHx is the enthalpy of combustion of the probable compound.
The following table shows the combustion enthalpies of the probable compounds and their deviation in relation to the enthalpy of ΔH = - 1280 kJ / mol
Compound Enthalpy of combustion (kJ/mol) Deviation
Methane - 890.7 43.8%
Ehylene -1411.2 9.3%
Ethanol -1368.6 6.5%
According to the previous table, we can say that the most probable compound is ethanol, since it has the smallest deviation in relation to the experimental enthalpy value of combustion.
Answer is: c. CuSO4 + 2NaOH yields Cu(OH)2 + Na2SO4.
Copper atom has oxidation number +2, sulfur atom oxidation number +6, oxygen has oxidation number-2, sodium has oxidation number +1 and hydrogen has +1 on both side of chemical reaction, so elements did not change their oxidation numbers.
Because of pollution from factories and other activities that release harmful gases into the air
Answer: It is an unsaturated solution
Explanation: This is because it has more solute than a normal solution.
