Answer:
1) rusting of metal is both chemical and physical change
2) black ice is an example of a physical change
Explanation:
when metal rusts, it is due to a reaction between the atoms in the metal and the atoms in the air(oxygen) or water(oxygen). When it rusts it also physically changes the look of the metal from silver to dirty brownish maroon.
Black ice is a change in state hence it cannot be a chemical change as the original substance NO LONGER EXISTS in a chemical reaction. It is a physical change however as the ice is changing into a different state of matter.
HOPE THIS HELPS!!!
Answer: The mass of aluminium sample is 55.4 gram
Explanation:
As we know that,
![m_1\times c\times (T_{final}-T_1)=-[m_2\times c\times (T_{final}-T_2)]](https://tex.z-dn.net/?f=m_1%5Ctimes%20c%5Ctimes%20%28T_%7Bfinal%7D-T_1%29%3D-%5Bm_2%5Ctimes%20c%5Ctimes%20%28T_%7Bfinal%7D-T_2%29%5D)
where,
= mass of aluminium = ?
= mass of water = 300.0 g
= final temperature = 
= temperature of aluminium = 
= temperature of water = 
= specific heat of aluminium = 
= specific heat of water = 
Now put all the given values in equation (1), we get
![-[m_1\times c_1\times (T_{final}-T_1)]=[m_2\times c_2\times (T_{final}-T_2)]](https://tex.z-dn.net/?f=-%5Bm_1%5Ctimes%20c_1%5Ctimes%20%28T_%7Bfinal%7D-T_1%29%5D%3D%5Bm_2%5Ctimes%20c_2%5Ctimes%20%28T_%7Bfinal%7D-T_2%29%5D)
![-[m_1\times 0.897\times (23.8-94.5)^0C]=[300.0g\times 4.184\times (23.8-21.0)]](https://tex.z-dn.net/?f=-%5Bm_1%5Ctimes%200.897%5Ctimes%20%2823.8-94.5%29%5E0C%5D%3D%5B300.0g%5Ctimes%204.184%5Ctimes%20%2823.8-21.0%29%5D)
Therefore, the mass of aluminium sample is 55.4 gram
Answer:
-1.42, -0.375, 32.5% (.325), 3/8 (.375), √4 (2.0), 3 (3.0), 2³ (8.0)
Answer:
How do ecosystems respond to natural disasters such as fires and floods :
Explanation:
They recover in stages, gradually returning to the original system. … She plans to create various physical and biological disturbances in the ecosystem to see how populations change over time.
