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.
Answer:
<h2>2 m/s²</h2>
Explanation:
The acceleration of an object given it's velocity and time taken can be found by using the formula
v is the velocity
t is the time taken
From the question we have
We have the final answer as
<h3>2 m/s²</h3>
Hope this helps you
Answer:
D) not swim in or drink the water from the stream
Explanation:
Low pH means the water is acidic which is harmful to your skin as it can cause burns and irritations. So any means of contacting with water is not healthy. The damage to the skin happens as in acidic water it has more H+ than in the neutral water and the extra H+ ions can ionize the atoms which are combined to form different compounds in the skin when in contact.
Answer:
An unbalanced force is a force that causes an object's state of motion to change. In other words, unbalanced forces are the things that make objects speed up or slow down.
Explanation:
(self-explanatory)
