You can see a physical change always but not always a chemical
Potential energy is energy due to an object's height above the ground.
Potential energy = mass x gravity x height
Kinetic energy is energy due to the motion of the object.
Kinetic energy = 1/2 x mass x velocity²
1.
The ball is not moving and is at a height above the ground so it has only potential energy.
P.E = 2 x 9.81 x 40
P.E = 784.8 J
2.
The ball is moving and has a height above the Earth's surface so it has both kinetic and potential energy.
P.E = same as part 1 = 784.8 J
K.E = 1/2 x 2 x 5²
K.E = 25 J
3.
The ball has no height above the Earth's surface and is moving so it has only kinetic energy.
K.E = 1/2 x 2 x 10²
K.E = 100 J
4.
50000 = 1/2 x 1000 x v²
v = 10 m/s
5.
39200 = 200 x 9.81 x h
h = 20.0 m
6.
12.5 = 1/2 x 1 x v²
v = 5 m/s
98 = 1 x 9.81 x h
h = 10.0 m
Answer:
b. transfer of electron(s).
Explanation:
An oxidation-reduction also called a redox reaction is a
chemical reaction in which electrons are transferred of between two species of reactants. It is a chemical reaction where the oxidation number of an atom, ion, or molecule, increases or decreases by losing or gaining electrons
The postulate of Dalton's atomic theory which is a result of the law of conservation of mass is: Atoms are indivisible particles, which can neither be created nor destroyed in a chemical reaction.
It may just be my internet but the picture is just white. maybe try reposting this..?