A new scientific method helps scientists form more efficient theories and models.
As new discoveries are made, existing theories are revised or replaced.
The atom has changed over time, and new theories must reflect those changes.
Scientists with different opinions
The answer is: As new discoveries are made, existing theories are revised or replaced.
Dalton stated that atom is matter that can not be divided.
His "plum pudding" model (1904) suggested: the electrons are embedded in the positive charge.
J. J. Thomson discovered the electron in 1897.
According to Rutherford model of the atom:
1) Atoms have their charge concentrated in a very small nucleus.
2) Major space in an atom is empty.
3) Atoms nucleus is surrounded by negatively charged particles called electrons.
4) An atom is electrically neutral.
What volume of oxygen gas is released at STP if 10.0 g of potassium chlorate is decomposed? (The molar mass of KClO3 is 122.55 g/mol.)
0.914 L
1.83 L
2.74 L
3.66 L
1. The balanced reaction would be:
2KClO3 --> 2KCl + 3O2
We are given the amount of potassium chlorate for the reaction. This will be the starting point of our calculation.
10.0 g KClO3 ( 1 mol KClO3 / 122.55 g KClO3) (3 mol O2 / 2 mol KClO3) = 0.1224 mol O2
V = nRT/P =0.1224 mol O2 x 273 K x 0.08206 atm L/mol K / 1 atm
V=2.74 L
Answer:
third option 2.74L
Answer:B & D
Explanation:
(3) The volume of each atom decreases.
(4) The frequency of collisions between atoms increases.
Answer is: (4) The frequency of collisions between atoms increases.
The average kinetic energy of molecules depends on the temperature.
As temperature increases, molecules gain more energy from surrounding and move faster and have more collisions.
Kinetic energy (standard unit is the joule J) depends on speed of the molecule.
Charles' Law (The Temperature-Volume Law) - the volume of a given amount of gas held at constant pressure is directly proportional to the Kelvin temperature:
V₁/T₁ = V₂/T₂.
When temperature goes up, the volume also goes up.
Answer: Yes, lead ion will react with potassium iodide.
Explanation: When lead ion reacts with KI, a bright yellow colored precipitate is formed.
The reaction of these two follows:
Hence, ion reacts with KI to yield
This test is the confirmatory test for lead ion which is present in Group I.