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
Answer:
V/V% = 8.2%
Explanation:
Given data:
Volume of methanol = 37.5 mL
Volume of solution = 456 mL
V/V% = ?
Solution:
V/V% = [volume of solute / volume of solution ]×100
V/V% = 37.5 mL / 456 mL × 100
V/V% = 0.08× 100
V/V% = 8.2%
B .combustion because HOH and CO2 are the products of complete combustion
Answer:
- Scientific question: does life exist on other planets?
- Non-scientific question: there are aliens that look like people?
Explanation:
A scientific question is a coherent question that can be used to develop a scientific hypothesis. Thus, a scientific question must be testable, verifiable, measurable and relevant to the topic of study. In the scientific method, the hypothesis is subsequently tested by experimental or observational procedures, where the results can be used to understand some particular aspect of the real world. On the other hand, a non-scientific question is a light conjecture which cannot be proved by using the scientific method.
Answer:
The correct answer to the question is
a. it contradicted accepted principles of physics
Explanation:
The idea of electrons moving in orbits contradict classical electromagnetism idea whereby electrons are expected spiral to the nucleus instantaneously. Meaning all atoms are supposed to be unstable a postulation that contradicts observable evidence.
Bohr's model of the atom consists of atoms, having electrons in specific orbits. The theory explains spectroscopy and enabled the determination of the constituent atoms present in distant stars.
