Answer:
- <u>1. Equation: 2x  + 3 = 9x - 11</u>
<u></u>
- <u>2. Each row has 2 chairs</u>
Explanation:
The variable x represents the number of chairs in each row.
<u />
<u>1. She can form 2 rows of a given length with 3 chairs left over.</u>
Thus, she has:
number of rows  number of chairs in      chairs             number of chairs
                              each row                       left over         she has
      2                        x                                    3                      2x + 3
<u>2.  She can form 9 rows of the same length if she gets 11 more chairs.</u>
That means that she is short in 11 chairs to have 9x chairs, or that she has 11 less chairs than 9x chairs. Then she has:
<u>3. Equation:</u>
Then, number of chairs she has is 2x + 3 and, also, 9x - 11, which allows to set the equation:
<u>4. Solve the equation:</u>
Therefore, each row has 2 chairs, and she has 2x + 3 = 4 + 3 = 7 chairs.
 
        
             
        
        
        
The balanced thermochemical equation is 
KBr ------- K + 1/2 Br2
<h3>What is thermochemical equation? </h3>
A Thermochemical Equation is defined as the balanced stoichiometric chemical equation which includes the enthalpy change, ΔH.
The chemical equation for the decomposition of potassium bromide to its constituent elements bromine ans potassium :
KBr ----- K + Br2
The balanced thermochemical equation of the decomposition of potassium bromide to its constituent elements potassium and bromide as follows
KBr ------- K + 1/2 Br2
As the heat is absorbed in this reaction therefore, heat is positive. 
Thus, we concluded that the balanced thermochemical equation is 
KBr ------- K + 1/2 Br2
learn more about thermochemical equation:
brainly.com/question/2733624
#SPJ4
 
        
             
        
        
        
Answer:
the dog barked is the answer
 
        
             
        
        
        
Answer:
 please the answer Is false
 
        
             
        
        
        
Explanation:
Given -
- An organic compound gives H₂ gas with Na 
- On treatment with alkaline iodine it gives yellow ppt. 
- On oxidation with CrO₃/H⁺ forms an aldehyde (C₂H₄O) 
To Find -
- Name the compound and write the reaction involved
Now, 
Let A be the organic compound. 
Then, 
- A + Na → + H₂↑
- A + I₂ → CHI₃ (yellow ppt.)
- A + CrO₃ + H⁺ → C₂H₄O
Now, 
Here we see that compound A reacts with chromic oxide (CrO₃) in the presence of acidic medium gives aldehyde.
- Functional group of aldehyde = —CHO
And It forms only 2 Carbon aldehyde it means, It is Ethanal (CH₃CHO).
Compound A reacts with chromic oxide (CrO₃) in the presence of acidic medium gives ethanal. 
It means, 
We know that 1° alcohol on oxidation gives aldehyde. 
Here it gives 2 Carbon aldehyde. 
It means,
Here 2 Carbon and 1° alcohol is used. 
Now, 
Its cleared that Compound A is Ethanol.
Reaction Involved -
- CH₃CH₂OH + Na → CH₃CH₂O⁻Na⁺ + H₂↑
- CH₃CH₂OH + I₂ + OH⁻ → CHI₃↓ + HCOO⁻ + HI + H₂O
- CH₃CH₂OH + CrO₃ + H⁺ → CH₃CHO