Answer:
In strict SI units (highly recommended), express n in moles, R is the universal gas constant R=8.314Jmol−K , T is the temperature in Kelvins, and the volume V is in m3 . The resulting pressure P will be in Pa. R=0.082054L−atmmol−K , in which case the pressure is calculated in atm.
We will use the expression for freezing point depression ∆Tf
∆Tf = i Kf m
Since we know that the freezing point of water is 0 degree Celsius, temperature change ∆Tf is
∆Tf = 0C - (-3°C) = 3°C
and the van't Hoff Factor i is approximately equal to 2 since one molecule of KCl in aqueous solution will produce one K+ ion and one Cl- ion:
KCl → K+ + Cl-
Therefore, the molality m of the solution can be calculated as
3 = 2 * 1.86 * m
m = 3 / (2 * 1.86)
m = 0.80 molal
<span>Answer is: the symbol is Cl.
[Ne ] 3s</span>² 3p⁶ is electric configuration of noble gas argon, neon (Ne) has10 electrons plus 6 electrons in 3s and 3p orbitals. Neutral atom of m<span>onatomic ion that has a charge of 1– has one electron less than argon, so that atom (chlorine) has 17 electrons. Charge of 1- means one electron more for ion: 17 + 1 = 18.
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