Answer:
NaOH
Explanation:
The sodium hydroxide is strongest base because it fully dissociate into ions.
It dissociate to gives the sodium and hydroxyl ions and solution became more basic.
NaOH → Na⁺(aq) + OH⁻(aq)
Its pH is 12. It is also known as caustic soda.
Other given Options:
The pH of blood is vary from 7.35 - 7.45. it is slightly alkaline.
The pH of HCl is 3.
The pH of saliva is 6.2 - 7.6.
We know that neutral pH is 7 the pH less than 7 is acidic so HCl is acidic because its pH is 3.
The pH is greater then 7 is basic so saliva and blood are basic but less than the NaOH.
Explanation:
Physical changes are the changes that does not lead to any change in chemical composition of a substance.
For example, mass, density, volume are all physical changes.
On the other hand, a change that leads to formation of a new compound by changing the chemical composition of reactants or combining atoms is known as a chemical change.
For example, combustion, toxicity, reactivity etc are all chemical changes.
Therefore, given changes are identified as follows.
- Coal burning : It is a combustion reaction. Hence, it is a chemical change.
- Ice melting : Physical state of water changes from solid to liquid. Hence, it is a physical change.
- mixing chocolate syrup with milk : No new compound is forming as there is no chemical reaction occurring. Hence, it is also a physical change.
- explosion of a firecracker : It shows reactivity of fire cracker. Hence, it is a chemical reaction.
- magnetizing of a screwdriver : It shows physical attraction between the magnet and screwdriver. Hence, it is a physical change.
You would use the formula for Boyle's Law:
(P1) (V1) = (P2) (V2)
(101.5) (2.0) = (P2?) (.75)
*P2 = 270kPa (You're allowed 2 significant figures)
P = Pressure
V = Volume
Milk is a complex colloidal system.
