Answer:
The octet rule is a chemical rule of thumb that reflects the observation that main group elements tend to bond in such a way that each atom has eight electrons in its valence shell, giving it the same electronic configuration as a noble gas
Explanation:
 
        
             
        
        
        
Answer:
<h2>         162g/mol</h2>
Explanation:
The question is incomplete. The complete question includes the information to find the empirical formula of nicotine:
<em>Nicotine has the formula   </em> <em> . To determine its composition, a sample is burned in excess oxygen, producing the following results:</em>
<em> . To determine its composition, a sample is burned in excess oxygen, producing the following results:</em>
<em>Assume that all the atoms in nicotine are present as products </em>
<h2>Solution</h2>
To find the empirical formula you need to find the moles of C, H, and N in each of the compound.
- 1.0 mol of CO₂ has 1.0 mol of C
- 0.70 mol of H₂O has 1.4 mol of H
- 0.20 mol of NO₂ has 0.20 mol of N
Thus, the ratio of moles is:
Divide all by the smallest number: 0.20
Hence, the empirical formula is C₅H₇N
Find the mass of 1 mole of units of the empirical formula:
Total mass = 60g + 7g + 14g = 81g
Two moles of units of the empirical formula weighs 2 × 81g = 162g and three units weighs 3 × 81g = 243 g.
Thus, since the molar mass is between 150 and 180 g/mol, the correct molar mass is 162g/mol and the molecular formula is twice the empirical formula: C₁₀H₁₄N₂.
 
        
             
        
        
        
Answer:
<h3><em>The process in which green plants prepare their food in their body by using minerals and carbon dioxide in the presence of sunlight .</em></h3><h3 /><h3 /><h3><em>Hope</em><em> it</em><em> </em><em>is </em><em>helpful</em><em> to</em><em> you</em><em> </em></h3><h3 />
 
        
             
        
        
        
The question is incomplete, the complete question is shown in the image attached to this answer.
Answer:
a) Br^-
b) FeCl3
c) slower
d) see the first attached image
Explanation:
Aromatic compounds undergo electrophilic substitution sections in the presence of the appropriate electrophile.
In the reaction above, the Br^- nucleophile attacks the Lewis acid FeCl3. Recall that the nitro group is meta directing hence the incoming Br^+ electrophile is directed towards the meta position as shown in the image attached.
Note that the nitro group deactivates the ring towards electrophilic substitution hence the reaction is slower with nitrobenzene than with unsubstituted benzene.
 
        
             
        
        
        
D) Physical Change, I would argue, because you can reverse this change by boiling off (evaporating) the water. But there are arguments for both physical and chemical change being what occurs. 
A physical change results in a change of the material's appearance, but no new chemical products result. A chemical change involves a chemical reaction, with new substances produced as a result of the change.