Answer:
Oxygen gas
Explanation:
Potassium chlorate KClO3 decomposes thermally to form potassium chloride KCl and oxygen gas is given off. This is in the presence of a catalyst, manganese iv oxide.
Hence, what is being said in essence is that when potassium chloride is heated in the presence of manganese iv oxide catalyst, oxygen is given off as the gaseous product with the formation of potassium chloride.
The chemical equation for the reaction is :
2KClO3 ——-> 2KCl + 3O2
This procedure is one of most important ways through which oxygen can be produced in the laboratory and can be used as a source of oxygen is industrial processes if on a large scale
Answer : The final temperature is, 
Explanation :
As we know that,
![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=m_1%5Ctimes%20c_1%5Ctimes%20%28T_%7Bfinal%7D-T_1%29%3D-%5Bm_2%5Ctimes%20c_2%5Ctimes%20%28T_%7Bfinal%7D-T_2%29%5D)
.................(1)
where,
q = heat absorbed or released
= mass of water at 
= 150 g
= mass of water at 
= 100 g
= final temperature = ?
= temperature of lead = 
= temperature of water = 
= same (for water)
Now put all the given values in equation (1), we get
![150\times (T_{final}-363)=-[100\times (T_{final}-303)]](https://tex.z-dn.net/?f=150%5Ctimes%20%28T_%7Bfinal%7D-363%29%3D-%5B100%5Ctimes%20%28T_%7Bfinal%7D-303%29%5D)
Therefore, the final temperature is,
Well cars need gas to run on if the car does not have gas it wont run and you cant get to places you need to go only if you have gas.
Salt lowers the freezing point, and thus the melting point of the ice
