Answer : Option D) 
Explanation : When a positron is getting absorbed it means it will be  so, the
 so, the  will get converted;
 will get converted;
So, the whole reaction will be;
 +
 +  ---->
 ---->  .
.
This will convert the whole element of Cu will get changed into Zn. As, it absorbs by the positron, the atomic number gets increased from 29 to 30.
 
        
             
        
        
        
The first one is 2
The second is 1
The third is 6
And the fourth is 3
        
             
        
        
        
Answer:
<h2>
<em>no</em></h2>
Explanation:
<h2><u><em>
the particles in gas move so freely that it cannot have a definite density</em></u></h2><h2><u><em>
</em></u></h2><h2><u><em>
</em></u></h2><h2><u><em>
</em></u></h2><h2><u><em>
moo</em></u></h2>
 
        
             
        
        
        
Note: Above question is incomplete: Complete question is read as 
<span>According the the arrhenius theory, which species does an acid produce in an aqueous solution?
</span>A) hydrogen ions B) hydroxyl ions C) Sodium ions D) Chloride ion
.....................................................................................................................
Correct answer for above question is A) Hydrogen ions
Reason:
According the Arrhenius theory of acid and base, acid generates hydrogen ions in aqueous medium, while bases generates hydroxyl ions in aqueous medium.  
Example of Acid:
HCl(aq)          →          H+(aq)    + Cl-(aq)
Example of Base:
NaOH(aq)           →          Na+(aq)       +     OH-(aq)
        
             
        
        
        
Answer:
1) The Kelvin temperature cannot be negative
2) The Kelvin degree is written as K, not ºK
Explanation:
The temperature of an object can be written using different temperature scales.
The two most important scales are:
- Celsius scale: the Celsius degree is indicated with ºC. It is based on the freezing point of water (placed at 0ºC) and the boiling point of water (100ºC).
- Kelvin scale: the Kelvin is indicated with K. it is based on the concept of "absolute zero" temperature, which is the temperature at which matter stops moving, and it is placed at zero Kelvin (0 K), so this scale cannot have negative temperatures, since 0 K is the lowest possible temperature.
The expression to convert from Celsius degrees to Kelvin is:

Therefore  in this problem, since the student reported a temperature of -3.5 ºK, the errors done are:
1) The Kelvin temperature cannot be negative
2) The Kelvin degree is written as K, not ºK