Answer:
Average atomic mass = 10.812 amu
Explanation:
The formula for the calculation of the average atomic mass is:
Given that:
<u>For first isotope, Boron-10:
</u>
% = 19.8 %
Mass = 10.013 amu
<u>For second isotope, Boron-11:
</u>
% = 80.2 %
Mass = 11.009 amu
Thus,
<u>Average atomic mass = 10.812 amu</u>
All of the questions here are pertaining to the colligative properties of a solution and the preparation of solutions. Maybe, it would be best if you understand the equations to be used in order to answer these questions.<span>
Freezing point depression or Boiling point elevation:
</span><span>ΔT = -K (m) (i)
</span>ΔT is the change in the freezing point or the boiling point not the freezing point/boiling point. Therefore, it should be added to the original value of the property of the solvent.
<span>
K is a constant called the molal freezing point depression constant and for the boiling point is the boiling point elevation constant. It is a property of the solvent.
</span><span>
m is the concentration of the solute in the solvent in terms of molality or kg solute/kg solvent.
</span><span>
i is the vant hoff factor which will represent the number of ions which the solute dissociates when in solution.</span>
1 - causes the molecules of the object or surface it strikes to vibrate faster, increasing its temperature.
2-carbon dioxide, methane, nitrous oxide, and water vapor it has to be one of these 3
3-The greenhouse effect is the way in which heat is trapped close to Earth's surface by “greenhouse gases.”
4- because of the fossil fuels that people are burning for energy.
5- due to human activities
Lambda = h\ Mv
lambda = 6.624 x 10^-34 / 9.1 x 10^-31 x 2.5 x 10^7
lambda = 2.9 x 10^-11 is your wavelength
Answer:
C8H8 + 10O2 → 8CO2 + 4H2O
Explanation:
unbalanced reaction:
C8H8 + O2 → CO2 + H2O
balanced for semireactions:
(1) 16H2O + C8H8 → 8CO2 + 40H+
(2) 10(4H+ + O2 → 2H2O)
⇒ 40H+ + 10O2 → 20H2O
(1) + (2):
balanced reaction:
⇒ C8H8 + 10O2 → 8CO2 + 4H2O
8 - C - 8
20 - O2 - 20
8 - H - 8