The mass of 2.80 grams of h2o is 18.02 amu I believe
Answer:
Your strategy here will be to use the molar mass of potassium bromide,
KBr
, as a conversion factor to help you find the mass of three moles of this compound.
So, a compound's molar mass essentially tells you the mass of one mole of said compound. Now, let's assume that you only have a periodic table to work with here.
Potassium bromide is an ionic compound that is made up of potassium cations,
K
+
, and bromide anions,
Br
−
. Essentially, one formula unit of potassium bromide contains a potassium atom and a bromine atom.
Use the periodic table to find the molar masses of these two elements. You will find
For K:
M
M
=
39.0963 g mol
−
1
For Br:
M
M
=
79.904 g mol
−
1
To get the molar mass of one formula unit of potassium bromide, add the molar masses of the two elements
M
M KBr
=
39.0963 g mol
−
1
+
79.904 g mol
−
1
≈
119 g mol
−
So, if one mole of potassium bromide has a mas of
119 g
m it follows that three moles will have a mass of
3
moles KBr
⋅
molar mass of KBr
119 g
1
mole KBr
=
357 g
You should round this off to one sig fig, since that is how many sig figs you have for the number of moles of potassium bromide, but I'll leave it rounded to two sig figs
mass of 3 moles of KBr
=
∣
∣
∣
∣
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
a
a
360 g
a
a
∣
∣
−−−−−−−−−
Explanation:
<em>a</em><em>n</em><em>s</em><em>w</em><em>e</em><em>r</em><em>:</em><em> </em><em>3</em><em>6</em><em>0</em><em> </em><em>g</em><em> </em>
It is an exothermic reaction
The molecular formula of the unknown compound is determined as C₉H₁₁NO₂.
<h3>Molecular formula of the compound</h3>
The molecular formula is calculated as follows;
CHNO + O₂ ------------> CO₂ + H₂O
Mass of carbon, C: = (6.64 x 12)/44 = 1.81 g in 2.77 g sample
Mass of hydrogen, H: = (1.67 x 2)/18 = 0.186 g in 2.77 g sample
Mass of Nitrogen, N: = (2.77 x 0.143)/1.69 = 0.234 g
Mass of oxygen, O: = 2.77 g - 1.81 g - 0.186 g - 0.234 g = 0.54 g
<h3>molar ratio of the elements: </h3>
C = 1.81 g = 0.15 mol
H = 0.186 g = 0.186 mol
N = 0.234 g = 0.017 mol
O = 0.54 g = 0.0337 mol
divide through with the smallest number of moles (0.017 mol);
C = 9
H = 11
N = 1
O = 2
Molecular formula = C₉H₁₁NO₂
Check the molar mass of the compound = (9 x 12) + (11 x 1) + (14) + (2 x 16) = 165 g/mol
Thus, the molecular formula of the unknown compound is determined as C₉H₁₁NO₂.
Learn more about molecular mass here: brainly.com/question/21334167
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Answer:
a-Interatomic bonds
Explanation:
First of all, it is not a force. Let alone be molecular force.
