Answer:
75.15 g/mol
Explanation:
First, let us look at the equation of reaction;
From the balanced equation of reaction, 1 mole of NaOH is required to completely neutralize 1 mole of HAA.
Recall that: mole = molarity x volume.
Therefore, 27.50 mL, 0.120 M NaOH = 0.0275 x 0.120 = 0.0033 moles
0.0033 mole of NaOH will therefore requires 0.0033 moles of HAA for complete neutralization.
In order to find the molar mass of the unknown amino acid, recall that:
<em>mole = mass/molar mass</em>, hence, <em>molar mass = mass/mole</em>.
Therefore, molar mass of HAA = 0.248/0.0033 = 75.15 g/mol
Answer:
1034.88J
Explanation:
Given that:
mass (m) = 11.2 g, initial temperature = 0°C, final temperature = 22°C, the specific heat capacity of water (C) = 4.2 J/g°C
Temperature difference (ΔT) = final temperature - initial temperature = 22 - 0 = 22°C
The quantity of heat (Q) required to melt the ice can be calculated from the equation:
Q = mCΔT
Q = 11.2 g × 4.2 J/g°C × 22°C
Q = 1034.88J
Answer:
yes
Explanation:
the metallic properties of elements tends to decrease across a period and increase down a group.
<span>C7H8
First, determine the number of relative moles of each element we have and the molar masses of the products.
atomic mass of carbon = 12.0107
atomic mass of hydrogen = 1.00794
atomic mass of oxygen = 15.999
Molar mass of CO2 = 12.0107 + 2 * 15.999 = 44.0087
Molar mass of H2O = 2 * 1.00794 + 15.999 = 18.01488
We have 5.27 mg of CO2, so
5.27 / 44.0087 = 0.119749 milli moles of CO2
And we have 1.23 mg of H2O, so
1.23 / 18.01488 = 0.068277 milli moles of H2O
Since there's 1 carbon atom per CO2 molecule, we have
0.119749 milli moles of carbon.
Since there's 2 hydrogen atoms per H2O molecules, we have
2 * 0.068277 = 0.136554 milli moles of hydrogen atoms.
Now we need to find a simple integer ratio that's close to
0.119749 / 0.136554 = 0.876937
Looking at all fractions n/m where n ranges from 1 to 10 and m ranges from 1 to 10, I find a closest match at 7/8 = 0.875 with an error of only 0.001937, the next closest match has an error over 6 times larger. So let's go with the 7/8 ratio.
The numerator in the ratio was for carbon atoms, and the denominator was for hydrogen. So the empirical formula for toluene is C7H8.</span>
