Answer:
All the above.
Explanation:
Energy is defined as the ability to do work. And changes in every occur in all changes of matter. Energy is neither created nor destroyed in these changes, but simply changes from on form to another.
A metal that would be magnetic is nickel
Yes, I mean it is the exhaust
Volume of Ammonia(NH₃) = 22.4 L
<h3>Further explanation</h3>
Given
Reaction
3CuO+2NH₃⇒ 3Cu + 3H₂O+ N₂
<em>In the problem, the CuO coefficient should be 3 not 2</em>
M CuO = 80
mass CuO = 120 g
Required
The volume of NH₃
Solution
mol CuO :
From the equation, mol ratio CuO : NH₃ = 3 : 2, so mol NH₃=
Assume at STP(0 °C, 1 atm) ⇒1 mol = 22.4 L, then volume of NH₃=22.4 L
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.
