Explanation:
A change that does not cause any change in chemical composition of a substance is known as a physical change.
For example, mass, density, volume etc are all physical changes.
On the other hand, a change that brings change in chemical composition of a substance is known as chemical change.
For example, combustion, toxicity, reactivity etc are all chemical changes.
Hence, following statements are identified as chemical or physical changes as follows.
(a) Oxygen gas supports combustion : Chemical change
(b) Fertilizers help to increase agricultural production : Chemical change
(c) Water boils below on top of a mountain : Physical change
(d) Lead is denser than aluminum : Physical change
(e) Uranium is a radioactive element : Chemical change
Answer:
<h2>The answer is 70 kPa</h2>Explanation:
In order to find the pressure if the volume were increased to 375 ml we use Boyle's law
That's
where
P1 is the initial pressure
P2 is the final pressure
V1 is the initial volume
V2 is the final volume
Since we are finding the final pressure
From the question
P1 = 105 kPa = 105 , 000 Pa
V1 = 250 mL
V2 = 375 mL
So we have
We have the final answer as
<h3>70 kPa</h3>Hope this helps you
Answer:
Covalent
Explanation:
Using an electronegativity chart, such as the attached one, you see that Nitrogen (N) has an electronegativity value of 3.0. Because both molecules are the same, 3.0-3.0=0. Therefore, because the electronegativity value difference is 0, the bond must be covalent.
