Answer:
C8H8O2
Explanation:
The molecular formula of a compound is simply a multiple of the empirical formula as shown below:
Molecular formula => [C4H4O]n
From the question given, we were told that molar mass of the compound is 136g/mol. This implies that:
[C4H4O]n = 136
Now, let us find the value of n in order to obtain the desired result. This is illustrated below:
[C4H4O]n = 136
[(12x4) + (4x1) + 16]n = 136
[48 + 4 + 16]n = 136
68n = 136
Divide both side by the coefficient of n i.e 68
n = 136/68
n = 2
Therefore the molecular formula is
=> [C4H4O]n
=> [C4H4O]2
=> C8H8O2
Answer:
a) 7
b) 4
c) 1
d) 4
Explanation:
Significant figures:
All non-zero digits are consider significant figures like 1, 2, 3, 4, 5, 6, 7, 8, 9.
Leading zeros are not consider as a significant figures. e.g. 0.03 in this number only one significant figure present which is 3.
Zero between the non zero digits are consider significant like 104 consist of three significant figures.
The zeros at the right side e.g 2400 are also significant. There are four significant figures are present.
A) 34.50698 g
In this measurement there are 7 significant figures.
B) 30.00 mL
There are 4 significant figures.
c) 0.0008 g
There is only one significant figure which is 8.
d) 125.0 °C
There are 4 significant figures.
Answer:
0.0099M = [F⁻]
Explanation:
<em>For BaF2, Ksp = 1.7x10⁻⁶</em>
<em />
When BaF₂ is in solution, the equilibrium between the solid and the dissociated ions occurs as follows:
BaF₂(s) ⇄ Ba²⁺(aq) + 2F⁻(aq)
Where Ksp = 1.7x10⁻⁶ is defined as:
1.7x10⁻⁶ = [Ba²⁺] [F⁻]²
<em>Where [] are equilibrium concentrations of each ion in solution.</em>
<em />
That means you will add F⁻ until its concentration exceeds:
1.7x10⁻⁶ = [0.0173] [F⁻]²
9.827x10⁻⁵ = [F⁻]²
<h3>0.0099M = [F⁻]</h3><h3 />
When more F⁻ is added, BaF₂ begins its precipitation.
Answer:
There are many errors possible while titrating the acid of an unknown concentration with a base like NaOH.
Main error that leads to the error in results is misreading of the end point volume .
End point is when the reaction between the analyte and solution of known concentration has stopped .
Sometimes Burette is not straight enough to read the volume of the end point. One way to misread the volume of burette is by looking at the burette volume at an angle .
From above , volume seems to be higher. Indicators are used to indicate the color change of the reaction. In Acid-Base titrations , indicators first lighten up then changes its color.
So, error may have occurred in wrongly judging of the end point by color change of the indicator .
The correct answer is: "3 (THREE)" .
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"HONC "
1 2 3 4
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In which "H" is the symbol for the element "hydrogen" ;
"O" is the symbol for the element "oxygen" ;
"N" is the symbol for the element "nitrogen" ;
"C" is the symbol for the element "carbon"
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And the number of bonds formed:
1, (for "H"); 2 (for "O"); 3 (for "N"); and 4 (for "C") .
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