Answer:
A chemical change
Explanation:
The marshmallow turning brown and bubbling implies that a chemical change has taken place.
For chemical changes to occur, we observe any of the following:
- a new kind of matter is formed.
- it is always accompanied by energy changes
- the process is not easily reversible
- it involves a change in mass
- requires considerable amount of energy.
ii. Two signs that shows a chemical change has taken place is that:
- bubbles are being formed as it is roasted and it implies that new substances have been formed.
- also, significant amount of heat energy is supplied for the roasting.
Answer:
They could possibly make daily check ups to the research facility?
Answer:
8.73
Explanation:
The concentration of acetic acid can be determined as follows:






Moles of
= 
=0.0090 moles
Moles of 
= 0.0090 moles
The equation for the reaction can be expressed as :
----->

Concentration of
ion = 
= 
= 0.052 M
Hydrolysis of
ion:
----->


⇒ 
= 
As K is so less, then x appears to be a very infinitesimal small number
0.052-x ≅ x





![[OH] = x =0.535*10^{-5}](https://tex.z-dn.net/?f=%5BOH%5D%20%3D%20x%20%3D0.535%2A10%5E%7B-5%7D)
![pOH = -log[OH^-]](https://tex.z-dn.net/?f=pOH%20%3D%20-log%5BOH%5E-%5D)
![pOH = -log[0.535*10^{-5}]](https://tex.z-dn.net/?f=pOH%20%3D%20-log%5B0.535%2A10%5E%7B-5%7D%5D)

pH = 14 - pOH
pH = 14 - 5.27
pH = 8.73
Hence, the pH of the titration mixture = 8.73