Answer:
mass of kI = 74.55 Atomic mass
74.55 g ---> 1 mole
48.9 g --> ?
48.9 / 72
0.7 mole.
In one mole of kI --->
Answer: The crest and trough of two waves intersect.
Explanation:
Answer:
B)
Explanation:
Electronic shell 2s2 2p6
Maximum level of electronic shell represents in which period is located that element
You would have to use the ideal gas law: PV = nRT where,
P = pressure
V = volume
n = moles
R = universal gas constant for a specific pressure (in this case it's 62.364 torr)
T = temperature in Kelvin
First, convert Celsius to kelvin by adding 273 to 25, which gives you 298K
Now plug in your variables to find n:
(800 torr)(1.25 L) = n(62.364)(298K)
1000 = 18584.472n
Now divide 1000 by 18584.472 to get n:
1000/18584.472 = 0.054 moles
The oxidation number of an element is the number of electrons that are gained or lost by the element to form a chemical bond.
the net oxidation number of the ion is its charge.
compound (NH₄)₂Cr₂O₇ is made of cation - NH₄⁺ and anion - Cr₂O₇²⁻
oxidation number of ion - -2
(oxidation number of Cr x 2 Cr atoms) +(oxidation number of O x 7 O atoms )= -2
oxidation number of Cr = y
oxidation number of O = -2
(y x 2) + (-2 x 7) = -2
2y - 14 = -2
2y = 12
y = + 6
therefore oxidation number of Cr is +6
