A formula unit is the same as the empirical formula of a compound or an ionic molecule. It is the lowest ratio of the atoms in the compound or ion. Zinc acetate ions dissociates into zinc ions and acetate ions. The dissociation reaction is expressed as follows:
Zn(O2CCH3)2 = Zn2+ + 2(O2CCH3)1-
We determine the amount of acetate ions produced as follows:
Moles Zn(O2CCH3)2 = (3 formula units Zn(O2CCH3)2) ( 1 mol / 6.022x10^23 formula units) = 4.98x10^-24 mol Zn(O2CCH3)2
moles (O2CCH3)1- = 4.98x10^-24 mol Zn(O2CCH3)2 ( 2 mol (O2CCH3)1- / 1 mol Zn(O2CCH3)2 ) = 9.96x10^-24 mol (O2CCH3)1-
# of acetate ions = 9.96x10^-24 mol (O2CCH3)1- ( 6.022x10^23 ions / 1 mol (O2CCH3)1-) = 6 acetate ions
Answer:
B)−6,942 J
/mol
Explanation:
At constant temperature and pressure, you cand define the change in Gibbs free energy, ΔG, as:
ΔG = ΔH - TΔS
Where ΔH is enthalpy, T absolute temperature and ΔS change in entropy.
Replacing (25°C = 273 + 25 = 298K; 25.45kJ/mol = 25450J/mol):
ΔG = ΔH - TΔS
ΔG = 25450J/mol - 298K×108.7J/molK
ΔG = -6942.6J/mol
Right solution is:
<h3>B)−6,942 J
/mol</h3>
H2SO4 is an acid
the chemical equation showing how H2SO4 is an acid according to the Arrhenius definition is as below
H2SO4 dissociate to give 2H^+ and SO4^2-
that is H2SO4 = 2H^+ + SO4^2-
According to Arrhenius an acid dissociate to give H^+ ions H2SO4 is an acid since it dissociate to give two hydrogen ions
Answer:
Gallium-72
Explanation:
The elements are identified by the number of protons of the atom, which is its atomic number.
In this case the number of protons 39 (atomic number 39) permit you to identify the element as gallium.
Now, to identify the isotope you tell the name of the element and add the mass number.
The mass number is the sum of the protons and the neutrons
In this case, the number of neutrons is the original 39 plus the 2 added suddenly, i.e. 39 + 2 = 41, so the mass number is 31 + 41 = 72
Therefore, the isotope is gallium - 72.
Answer ; The correct answer is : 346 m/s .
Sound is a type of longitudinal wave , which is produced when a matter compress or refracts .
Speed of sounds depends on factors like medium , density , temperature etc .
Effect of Temperature on speed of sounds :
When the temperature increases , molecules gains energy and they starts vibrating and with higher temperature vibration becomes fast . So the waves of sounds can travel faster due to faster vibrations . Hence , speed of sounds is directly proportional to the temperature or speed of sounds increases with increase in temperature .
The speed of sounds at 0⁰C is 331 
The relation between speed of sound and temperature is given as :
Given : Temperature = 25 ⁰ C
Plugging values in formula =>
