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
The answer for the following question is option "C".
Option C is not included in the John Dalton's modern theory of an atom.
- "It states atoms of different elements combine to form new compound" but not new elements
Explanation:
According to John's Dalton's modern theory of an atom:
1. All matter is composed of atoms.
2. Atoms cannot be created,destroyed or subdivided in the ordinary chemical reactions.
3. Atoms of one element differ in the properties from atoms of an another element.
(i.e.)Each and every atom of the element has its own unique properties of their own.
4. Atoms of one element combine with the atoms of another element to <u>form new compound.</u>
5. Atoms that make up an element are identical to each other.
<u>Given:</u>
Enthalpy change (ΔH) for SO3 decomposition = +790 kJ
Moles of SO3 = 2.1 moles
<u>To determine:</u>
Energy required when 2.1 moles of SO3 reacts
<u>Explanation:</u>
The decomposition reaction is -
2SO3(g) → 2S(s) + 3O2 (g)
Energy required when 2 moles of SO3 reacts is 790 kJ
Thus, for 2.1 moles of SO3 the energy requirement would be
= 2.1 moles SO3 * 790 kJ/2 moles SO3 = 829.5 kJ
Ans: 830 kJ are required when 2.1 moles of SO3 reacts.
Polar Covalent is the name used to describe bonds that have both ionic and covalent character because the electrons are shared unequally. The Pauling Scale is used to assign electronegativity to atoms. It ranges from to 4.00 (fluorine).
Answer:
copper, 8930.
Explanation:
Copper is a chemical element with the symbol Cu (from Latin: cuprum) and atomic number 29. to сuprum (Latin). Coper (Old English) and copper were derived from this, the later spelling first used around 1530. muscle, and bone. The adult body contains between 1.4 and 2.1 mg of copper per kilogram of body weight.
