A) 0 because Fe is uncharged
b) 0 because O in O2 is uncharged as well
c) +3 because each Fe atom lost 3 electrons
d) -2 because each oxygen aim gained 2 elections
Answer:
The number of mole is 2.422 moles
Explanation:
To calculate the number of mole, we have to use the formula n = m /Mm
n - moles
m - mass
Mm - molar mass
Let's calculate the molar mass of the compound SiO2
Si - 28.0855
O - 15.999
Note: there are two atoms of oxygen in the compound
Mm of SiO2= 28.0855+ 2* 15.999
= 60.0835g/mol
Now, we calculate the number of moles
n = 145.54g/ 60.0835g/mol
= 2.422mol
Holonium and Gadolinium has the highest number of neutrons in the nucleus.
Looking at the atoms listed;
Dysprosium has 66 protons
Holonium has 67 protons
Neodymium has 60 protons
Europium has 63 protons
Gadolinium has 64 protons
Then,
Number of neutrons = Mass number - number of protons
For Dysprosium
157 - 66 = 91 neutrons
For Holonium
162 - 67 = 95 neutrons
For Neodymium
149 - 60 = 89 neutrons
For Europium
148 - 63 = 85 neutrons
For Gadolinium
159 - 64 = 95 neutrons
Hence, Holonium and Gadolinium has the highest number of neutrons in the nucleus.
Learn more: brainly.com/question/14156701
Answer:
1.0 × 10⁻⁵ mol/L
Explanation:
The concentration of a gas (C) in a liquid depends on its partial pressure (P), as expressed in Henry's law.
C = k × P
where,
k is the henry's law constant
When the partial pressure of the gas equilibrates at 3.0 × 10⁻⁴ atm, its concentration in the liquid is:
C = k × P
C = 3.4 × 10⁻² mol/L.atm × 3.0 × 10⁻⁴ atm
C = 1.0 × 10⁻⁵ mol/L
Answer= C) CN contains a covalent bond.