Answer:
1.35 g
Explanation:
Data Given:
mass of Potassium Permagnate (KMnO₄) = 3.34 g
Mass of Oxygen: ?
Solution:
First find the percentage composition of Oxygen in Potassium Permagnate (KMnO₄)
So,
Molar Mass of KMnO₄ = 39 + 55 + 4(16)
Molar Mass of KMnO₄ = 158 g/mol
Calculate the mole percent composition of Oxygen in Potassium Permagnate (KMnO₄).
Mass contributed by Oxygen (O) = 4 (16) = 64 g
Since the percentage of compound is 100
So,
Percent of Oxygen (O) = 64 / 158 x 100
Percent of Oxygen (O) = 40.5 %
It means that for ever gram of Potassium Permagnate (KMnO₄) there is 0.405 g of Oxygen (O) is present.
So,
for the 3.34 grams of Potassium Permagnate (KMnO₄) the mass of Oxygen will be
mass of Oxygen (O) = 0.405 x 3.34 g
mass of Oxygen (O) = 1.35 g
First , 27.6 cm^3 is equal to 27.6 ml
Density = mass g / volume cm^3
= 74.6 / 27.6 = ........ g/cm^3
Answer:
Atomic number is the number of protons in an isotope or element.
Explanation: The atomic number is the same number of protons in an element or isotope and if said isotope is neutral than it is the same number of electrons.
Example: Atomic number = 19 Protons = 19 if neutral Electrons = 19
Answer:
It's Al 3+ + 3e - → Al
Explanation:
Because three negatively charged electrons are needed to balance the three positive charges on the aluminum ion
Number of neutrons = Atomic mass - Atomic number (number of protons)
Hope that helps!