Answer:
20 neutrons
Explanation:
neutrons = mass number - atomic number
mass number = 39, atomic number = 19
neutrons = 39 - 19 = 20
Answer:
D: Atmospheric pressure is greater than vapor pressure,and water molecules escape from the solution into the air.
Explanation:
More is the electronegativity of atoms attached to the alpha carbon atom more will be the attraction of electron towards it. As a result, release of hydrogen ion will be easier.
Therefore, there will be increased in acidity of the compound.
Since, fluorine, chlorine and bromine are all group 17 elements and fluorine is more reactive than chlorine. On the other hand, chlorine is more reactive than bromine.
Hence, ability to attract the electrons towards itself will be maximum in fluorine and least in bromine.
Therefore, decreasing order of acidity of the given compounds is as follows.
> > >
Zinc oxide and zinc sulfide react with HCl: ZnS(s) + 2 HCl(aq) > ZnCl2(aq) + H2S(g)
Answer:
Answer A
Explanation:
2 H2 + O2 = 2 H2O
knowing the mole weights of these elements shows O2 is the limiting reactant in this situation.
4 g oxygen is 4 /31.998 = .125 mole O2
We should get two times these moles of water = .250 moles
weight = .250 (1.008 * 2 + 15.999) = 4.50 gm H20 (theoretical)
....but we only got 4 gm
4/4.50 = 88.8%