Answer:
A. to cure human diseases
Explanation:
Answer:B
Explanation: A chemical change is something that is irreversible
Answer:
<em>the <u>valency of an element</u> is its combining capacity that is the number of electrons it requires to lose, gain or share in order to become neutral.</em>
[ An element can become neutral if it completes it's octet. That is if an element has 8 electrons in it'd outermost shell then it is considered neutral ]
- The valence of Magnesium is 2 because it requires to lose 2 electrons to become neutral.
- whereas, the valence of Oxygen is 2 because it needs to gain 2 electrons to become stable.
Hence they both have the same valence.
One may say that oxygen's valence is -2 while that of Magnesium is + 2. It's meaning is still the same but "-" sign indicates that oxygen will be gaining electrons in the process of becoming stable.
form the molar concentration of the Ca(OH)2 which is a base we can deduct the pOH
pOH=-lg[OH-]
[OH-]=8.8 x 10-4 M
pOH=4
pH=14-pOH
pH=10
-lg[H+]=10
[H+]=10^-10
Answer:
both will be at liquid state. the particles will move rapidly in all directions and will collide with other particles in random motion
