Answer: The metal that has a greater reactivity is more easily oxidized.
Explanation:
Oxidation is when the elements lose electrons and increase their oxidation state.
The metals tend to react by losing electrons and form the corresponding cation.
For expample, sodium (an alkalyne metal) loses one elecron and form the cation Na¹⁺ , then this cation combine with an anion and form compounds like NaCl, NaOH. The same do the other alkalyne metals.
Magnesium (an alkalyne earth metal) loses two electrons and form the cation Mg²⁺, then it combines with some anions to form compounds, like MgSO₄, Mg(OH)₂.
So, the easier the metal gets oxidized the greater its reactivity.
If you placed the contents of a packet of powdered iced tea mix into a bottle of water and shook it, D. The solution would be homogenous if half of the powdered solute sat at the bottom of the bottle.
Explanation:
- Evaporation is defined as a process in which liquid state of water is changing into vapor state.
So, we need to break the bonds of liquid substance in order to convert it into vapor state. And, energy is absorbed for breaking of bonds which means that evaporation is an endothermic process.
Hence, the statement evaporation of water is an exothermic process is false.
- When a hydrocarbon reacts with oxygen and leads to the formation of carbon dioxide and water then this type of reaction is known as combustion reaction.
A combustion reaction will always release heat energy. Hence, combustion reaction is exothermic in nature.
- When energy is transferred as heat from the surroundings to the system then it means energy is being absorbed by the system. And, absorption of heat is an endothermic process for which
is positive.
- Whereas when energy is transferred from system to the surrounding then it means energy is released by the system which is an exothermic process.
Hence, for an exothermic process value of
is negative.
Thus, we can conclude that statements which are true are as follows.
- A combustion reaction is exothermic.
- When energy is transferred as heat from the system to the surroundings,
is negative.
- For an endothermic reaction Deta H is positive.
Answer: a) 
b) 
Explanation:
The reaction is :

Rate = Rate of disappearance of
= Rate of appearance of
Rate =
= ![\frac{d[NO_2]}{4dt}](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5BNO_2%5D%7D%7B4dt%7D)
Rate of disappearance of
=
= 
a) Rate of disappearance of
= ![-\frac{d[N_2O_5]}{2dt}](https://tex.z-dn.net/?f=-%5Cfrac%7Bd%5BN_2O_5%5D%7D%7B2dt%7D)
Rate of appearance of
= ![\frac{d[NO_2]}{4dt}](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5BNO_2%5D%7D%7B4dt%7D)
b) Rate of appearance of
= ![\frac{d[NO_2]}{dt}=2\times 1.7\times 10^{-4}}=3.4\times 10^{-4}](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5BNO_2%5D%7D%7Bdt%7D%3D2%5Ctimes%201.7%5Ctimes%2010%5E%7B-4%7D%7D%3D3.4%5Ctimes%2010%5E%7B-4%7D)