Answer:
B. Anions are formed when an atom loses electrons.
<span>Planck’s constant relates the
joules of energy absorbed/released by matter to the wave frequency f. the
plancks constant was first recognized in 1900 by Max Planck. The equation that
relates the joules of energy absorbed/released by matter to the wave frequency
f is called the plancks-eintein relation, E = hf</span>
Answer:
The enthalpy of combustion of ethanol in kJ/mol is -1419.58 kJ/mol.
Explanation:
The heat absorbed by the bomb and water is equal to the product of the heat capacity and the temperature change. Working with this equation, and assuming no heat is lost to the surroundings, we write
:
qcal= Ccal × ΔT= 490 J/K × 276.7 K= <u>135,583 J</u> = 135.58 kJ
Note we expressed the temperature change in K, because the heat capacity is written in K.
<u>
Now that we have the heat of combustion, we need to calculate the molar heat. </u>
Because qsystem = qrxn + qcal and qrxn = -qcal, the heat change of the reaction is -135.58 kJ.
This is the heat released by the combustion of 4.40 g of ethanol ; therefore, we can write the <u>conversion factor as 135.58 kJ/ 4.40 g</u>.
The molar mass of ethanol is 46.07 g, so the heat of combustion of 1 mole of ethanol is
:
molar heat of combustion= -135.58 kJ/4.40 g x 46.07 g/ 1 mol= -1419.58 kJ/mol
Therefore, the enthalpy of combustion of ethanol in kJ/mol is -1419.58 kJ/mol.
A solvent (from the Latin solvō, "I loosen, untie, I solve") is a substance that dissolves a solute (a chemically distinct liquid, solid or gas), resulting in a solution. A solvent is usually a liquid but can also be a solid or a gas. The quantity of solute that can dissolve in a specific volume of solvent varies with temperature. Common uses for organic solvents are in dry cleaning (e.g., tetrachloroethylene), as paint thinners (e.g., toluene, turpentine), as nail polish removers and glue solvents (acetone, methyl acetate, ethyl acetate), in spot removers (e.g., hexane, petrol ether), in detergents (citrus terpenes) and in perfumes (ethanol). Water is a solvent for polar molecules and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within a cell. Solvents find various applications in chemical, pharmaceutical, oil, and gas industries, including in chemical syntheses and purification processes.
source: wikapedia
Answer: The Answer is B. Energy can not be created nor destroyed.
Explanation:
