Answer:
-179.06 kJ
Explanation:
Let's consider the following balanced reaction.
HCl(g) + NaOH(s) ⟶ NaCl(s) + H₂O(l)
We can calculate the standard enthalpy change for the reaction (ΔH°r) using the following expression.
ΔH°r = 1 mol × ΔH°f(NaCl(s)) + 1 mol × ΔH°f(H₂O(l)) - 1 mol × ΔH°f(HCl(g)) - 1 mol × ΔH°f(NaOH(s))
ΔH°r = 1 mol × (-411.15 kJ/mol) + 1 mol × (-285.83 kJ/mol) - 1 mol × (-92.31 kJ/mol) - 1 mol × (-425.61 kJ/mol)
ΔH°r = -179.06 kJ
Answer:
I know that the 100-mL graduated cylinders are always read to 1 decimal place.
I think for 50 mL graduated cylinders, it lets you measure volumes up to 50.0 mL to the nearest 0.1 or 0.2 mL, depending on your exact cylinder.
Potassium sulfide, also
known as dipotassium monosulfide, consists of two potassium ions bonded to a
sulfide atom, rendering the chemical formula K2S.<span>Rarely
found in nature due to its high reactivity with water, potassium sulfide is
refined from the more common potassium sulfate (K2SO4) and is used in many
industries</span>
Answer:
The same genes or slightly different versions of the same gene can be found on each chromosome in a pair. They form a line and split off bits of themselves, which they barter with one another. In sexual reproduction, crossing over is the first method that genes are shuffled to develop genetic variation.
From the periodic table:
mass of carbon = 12 grams
mass of hydrogen = 1 gram
mass of nitrogen = 14 grams
mass of oxygen = 16 grams
mass of chlorine = 35.5 grams
Therefore,
molar mass of <span>c17h22clno4 = 17(12) + 22(1) + 35.5 + 14 + 4(16) = 339.5 grams
number of moles = mass / molar mass
number of moles = (23*10^-3) / (339.5)
number of moles = 6.77 * 10^-5 moles
number of atoms = number of moles * Avogadro's number
number of atoms = 6.77*10^-5 * 6.022*10^-23
number of atoms = 4.079 * 10^-27 atoms</span>