Answer:
- a change in color
- the formation of a precipitate
- the formation of bubbles
Explanation:
In a chemical reaction, there is always a rearrangement of atoms within the molecules of reactants to form new products. Such a change is different from changes in the physical form of molecules, e.g. shape.
Thus, according to this criteria, only three options are correct in the given question. A change in color is definitely an indication of chemical reaction because the emission of light before and after cannot be changed unless molecules are rearranged to form a new chemical. Likewise, precipitates form when a reaction takes place between chemically dissolved molecules to form less or not dissolvable compounds. In the end, the configuration of bubbles also indicates that the reaction has taken place because new gases are being released.
On the other hand, change in shape is a physical change because the composition doesn't need to also been changed. An example is the ice formation from water. Same is the case with "change of clear liquid to cloudy" because the addition of non-reactive substances could change the nature of liquid to cloudy however the reaction doesn't need to have taken place.
Matter can be many things, but is mostly made of atoms. Atoms are small things that cannot be seen directly, as lights either passes through it or alters it. However, we know that atoms are made of 3 parts, those being the proton, neutron, and electron.
Protons have a positive electromagnetic charge.
Neutrons have no charge.
Electrons have a negative charge equal to the protons positive charge.
Protons and neutrons make up what's called the nucleus, which is orbited by the electrons.
Protons and neutrons also share another thing in common, that being their composition.
Until relatively recently, we thought that these were the smallest particles in the universe, and indestructible. However, modern discoveries have revealed that they are actually made of quarks and gluons.
These are actually indestructible, being part of the group that is elementary particles.
Answer:
2632 foot-pound
Explanation:
Work done: Work is said to be done when ever a force moves a body through a given distance. The S.I unit of force is Newton (N).
From the question,
The expression for work done is given as,
W = Fdcos∅......................... Equation 1
Where W = work done, F = force, d = distance, ∅ = angle between the force and the horizontal.
Given: F = 32 lbs, d = 90 feet, ∅ = 24°
substitute into equation 1
W = 32×90×cos24
W = 2880(0.914)
W = 2632.32
W = 2632 foot-pound
Answer:
True
Explanation:
Magnetic field lines outside of a permanent magnet always run from the north magnetic pole to the south magnetic pole. Therefore, the magnetic field lines of the earth run from the southern geographic hemisphere towards the northern geographic hemisphere.
Yes they are balanced because if it has 10 Newtons to the right and then someone pushes 5 Newtons to the left and then another 5 then that means there is 10 Newtons left and 10 Newtons right